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INTERNATIONAL JOURNAL OF RESEARCH AND INNOVATION IN APPLIED SCIENCE (IJRIAS)
ISSN No. 2454-6194 | DOI: 10.51584/IJRIAS |Volume X Issue X October 2025
The Microstructure and Mechanical Properties of the Ball-Milled Al-
Mn-Zr Alloys with Ce and Y Additions
Eshetu Mentesenot A., Lekeka Biniam B., Tasisa Dawit M., and Fenta Haftamu T.
Department of Advanced Materials Science, MISIS University, Russia
DOI: https://doi.org/10.51584/IJRIAS.2025.1010000030
Received: 26 Sep 2025; Accepted: 02 Oct 2025; Published: 30 October 2025
ABSTRACT
Mechanical alloying (MA), hot press sintering (HPS), and post-annealing were used to create high-
performance Al-Mn-Zr-based quaternary alloys containing the rare earth (RE) elements Ce and Y. Three alloy
compositions (Al-4Mn-1,2Zr, Al-4Mn-1,2Zr-0,6Y, and Al-4Mn-1,2Zr-0,6Ce (at.%)) were high energy ball
milled for 10 h, consolidated at 350 °C or 450 °C and subsequently annealed at 350-450 °C for periods ranging
from 15 minutes to 4 hours’ analysis of crystallite size supported the extensive grain refinement during milling
(16--20 nm), whereas compaction at temperatures at 450 caused a notable grain coarsening (up to 84 nm. SEM-
EDS elemental mapping revealed precipitation free zones and intermetallic-rich zones, indicating precipitates
formation during thermal processing. After milling, Al solid solution and Al4Mn for Al-Mn-Zr and Al-Mn-Zr-
Y alloys, Al6Mn phase for Al-Mn-Zr-Ce alloy were revealed. After sintering Al6Mn and Al3Zr phases
precipitated for all alloys studied.
According to the compression tests, the addition of Ce and Y to Al-Mn-Zr alloys varies in composition and
heat treatment. Ce-containing alloys have high ultimate compression strength (UCS) and ductility, while Y-
modified alloys balance strength and ductility. Annealing for 1-4 hours at 400°C gave maximum values for Al-
4Mn-1,2Zr. The alloy also had maximum microhardness and macro-hardness after annealing (~430 HV and
370 HV) respectively. Annealing led to a rise in hardness for Ce and Y alloys from about (~ 250-280) HV to
more than ~350 HV. Sintering pieces at 450 °C produced nearly the ideal density which shows an improved
packing of the structure. Still, keeping the samples at 450°C for a long period following mild pressing caused
the grains to become coarse and diminished the ability to restore their properties.
High alloyed Al-Mn-Zr based alloys exhibited superior strength properties and Y/Ce increased ductility. It is
shown in the study that the MA-HPS process can successfully design high-performance Al alloys and has
implications for lightweight parts.
INTRODUCTION
The hunt for high-performance materials that can survive extreme temperatures has prompted substantial
research into advanced alloy systems, notably those based on aluminum [1].Many engineers have paid close
attention to aluminum-based alloys because of their remarkable features and ability to be used in a variety of
ways. Because aluminum is light, has great strength and resists rust, it can effectively be mixed with other
elements. Their useful qualities in mechanical, thermal and electrical areas allow them to be used in many
fields., since the need for high-performance materials is increasing, it is becoming necessary to use alloying
elements besides the typical manganese and zirconium. The performance of aluminum alloys might be
improved using Cerium and Yttrium (Ce and Y) in the research.
Conventional aluminum alloys frequently fail to fulfill the demanding demands of increased temperature
applications, necessitating the development of innovative alloy compositions and processing techniques to
overcome these constraints [2] Mechanical alloying, a solid-state powder metallurgy process, has emerged as a
potent tool for synthesizing complex alloy systems with higher microstructural control and better
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characteristics. This method allows production of homogeneous alloys, with refined grain structures, and long
solid solubilities, resulting in a greater strength, hardness and thermal stability. The properties of aluminum
alloys are further enhanced by the addition of alloying elements, e.g. manganese and rare earth metals, which
strengthening effects can be solid solution strengthening, precipitation hardening, and grain boundary pinning
[3].
Aim
To Determine the influence of Ce and Y Additions and high energy ball milling treatment on the
Microstructure and Mechanical Properties of the Al-Mn-Zr alloys to develop high-strength materials capable
of performing at elevated temperatures.
Objectives:
Analyze the powder particles size, microhardness, phase composition, grain size of the aluminum based solid
solution after milling.
Analyze the influence of annealing time and temperature on hardness, microhardness, and density of the hot-
press sintered alloys.
Investigate the phase composition, grain size and hardness evolution in alloys sintered at 350 and 450 °C and
further heat treatment.
Examine the effect of Ce and Y on the microstructure, mechanical properties and phase composition of Al-Mn-
Zr alloys to determine the perspective alloys compositions and treatment.
LITERATURE REVIEW
Introduction to Aluminum alloys
Engineers often choose aluminum alloys since they are light, not easily corroded, and strong. These metals are
split into wrought and cast alloys. Wrought alloys in the Al-Mn group are valued because they are both flexible
and sturdy [4] Manganese (Mn) gives the alloys greater resistance to corrosion and strengthens solid solutions,
while rare earth elements including lanthanum (La).Because cerium (Ce) and neodymium (Nd) make grain
structure finer and improve thermal stability [5]. Aluminum-alloys are now more popular in industry. The good
points about these materials are their strength compared to weight, simple processing, being flexible, excellent
heat conduction, resisting rust, and a pleasant natural look. Aluminum alloys are flexible to use as they can be
easily made into any shape, allowing for complex cross-sectional geometries. Certain important properties of
aluminum alloys are functions of chemical composition, microstructure, and processing history. Their density
is 2.7 g/cm 3, which makes them light and useful in aerospace and automotive applications. They are also good
in corrosion resistance dating back to their thin oxide layer which makes them useful in marine and chemical
processing. Moreover, alloys that contain alloying elements such as copper, magnesium, and zinc are much
stronger and hence used widely in aerospace structures [6].
Aluminum alloys are grouped into two broad categories; wrought alloys and cast alloys. This is represented in
fig. 1 wherein the Aluminum alloys are classified with the wrought alloys further divided into heat-treatable
and non-heat-treatable alloys, and the cast alloys being divided based on their main alloying agents.
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Figure 1 – Classification of aluminum alloys [7]
Wrought Alloys produced through mechanical working (rolling, extrusion. forging). Applications of these
types of alloys normally involve areas that need high strength and ductility. The most important wrought alloys
are the 1xxx series (pure aluminum), the 2xxx (Al-Cu), the 5xxx (Al-Mg), and 7xxx (Al-Zn) series. An
extremely good example of which is the Al-Mn (3xxx) series where manganese is a major alloying addition,
and which is widely utilized in beverage cans, and heat exchangers due to its good corrosion resistance, and
formability [4].
Cast Alloys: Suitable for processes like sand casting, die casting and investment casting. They are usually used
in applications where complex shapes and good machinability are needed. The 2xx are common cast alloys.
2xx.x (Al-Cu), 3xx. x (Al-Si-Cu), and 5xx.x (Al-Mg) series. Silicon (Si) is added to cast alloys to enhance
their fluidity and decrease the solidification shrinkage, such properties make them suitable for automotive parts
such as engine blocks and cylinder heads [8].
Recent advancements in technology, including additive manufacturing (3D printing) and direct metal laser
sintering (DMLS), have greatly improved aluminum alloy properties and applications. These techniques enable
the production of complex aluminum alloy components with custom microstructures and characteristics,
making them especially useful in aerospace and automotive applications [9] The process illustrated by Figure 2
begins with melting and fusing metal powders by using a laser or electron beam. It takes as inputs the standard
Al7075 power feedstock and those that have been processed with nanoparticles. Nanoparticles encourage
different and even grain growth, which lessens the weight of the strain from solidification. Using this method,
alloys do not develop hot cracks and are designed in the best possible way.
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Figure 2 – Recent advancement in technology of aluminum alloys [10]
Nanostructured Aluminum Alloys: The creation of nanostructured aluminum alloys has resulted in
considerable increases in strength, hardness, and thermal stability. These alloys are created by advanced
processing techniques like severe plastic deformation (SPD) and mechanical alloying [9].
Recycling and Sustainability: Recent advances in recycling technology have enhanced the quality and
characteristics of recycled aluminum alloys. Solid-state recycling and melt purification techniques have
decreased contaminants in recycled aluminum and improved its mechanical characteristics. The advancement
of high-temperature aluminum alloys with higher thermal stability and creep resistance has increased their use
in the aerospace and automotive industries. These alloys are created by combining alloying elements like
zirconium (Zr) and scandium (Sc), which generate stable precipitates at high temperatures [11].
Role and properties of Alloying Element
The addition of alloying materials significantly alters the properties of aluminum alloys.
Manganese (Mn)
Manganese is a key alloying element in the 3xxx series of alloys, increasing strength and corrosion resistance
through the formation of tiny dispersoids during solidification. Additionally, Mn improves the work-hardening
ability of aluminum alloys, making them ideal for high-ductility applications [12].
Copper (Cu)
Copper is the main alloying element in the 2xxx series alloys. It greatly boosts strength by forming
precipitates like Al2Cu during aging. However, Cu decreases corrosion resistance, limiting the use of these
alloys in some situations [4].
Zirconium
Zirconium is a common additive to aluminum and alloys, with its solubleness in aluminum at 660 °C. Adding
0.02–0.2 wt.% increases strength by nearly three times and maintains properties up to 300 °C. It also enhances
resistance to fatigue, corrosion, and natural aging [12] [13].
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Zinc (Zn)
Zinc is the main alloying ingredient in the 7xxx series alloys. It produces precipitates like as MgZn2 during the
aging process, which considerably enhances strength. These alloys are commonly utilized in aeronautical
applications due to their high strength-to-weight ratio [14].
Rare Earth (RE)
Rare earth Elements optimize grain structure, improve thermal stability, and improve mechanical qualities like
hardness and tensile strength For example, [5] found that adding RE components to Al-Mn-Cu-Zr alloys
resulted in a fine-grained microstructure with higher mechanical properties.
Yttrium
Yttrium, a rare earth (RE) element, improves thermal stability and oxidation resistance in aluminum alloys.
[15] found that nanoscale Al₃Y precipitates restrict grain formation at high temperatures and improve creep
resistance. Yttrium also improves microstructure by inhibiting recrystallization, making it suitable for high-
temperature aerospace applications [16].
Cerium
Cerium is another RE element that greatly enhances mechanical strength and corrosion resistance in aluminum
alloys. It produces Al-Ce intermetallic (e.g., Al₁₁Ce₃) that are thermally stable up to 300-400 °C, preventing
over-aging [17] Ce also improves castability by lowering hot cracking and increasing fluidity, making it
excellent for additive manufacturing of high-performance Al alloys [18].
Significance of High Alloyed Al-Mn-RE Alloys
High-alloyed Al-Mn-RE alloys have garnered significant attention due to their exceptional mechanical
properties, corrosion resistance, and suitability for high-temperature applications. Figure 3 illustrates
Application and significance of high alloyed Al alloys These alloys are widely used in aerospace, automotive,
and structural engineering industries, where lightweight materials with high strength and durability are
essential [4] [8].
Figure 3 – Application and significance of high alloyed Al alloys [19]
The incorporation of RE elements into Al-Mn alloys has been shown to significantly improve mechanical
properties, such as hardness, tensile strength, and fatigue resistance. For instance, [20] demonstrated that high-
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energy ball milling followed by hot-press sintering results in a fine-grained microstructure with enhanced
mechanical properties. However, challenges remain in optimizing the alloy composition and processing
parameters to achieve consistent performance in high-temperature environments [21].
Improved mechanical properties
Al-Mn alloys gain increased hardness, tensile strength and fatigue resistance when they are mixed with rare
earth (RE) elements. Lanthanum (La), cerium (Ce) and neodymium (Nd) in REs are thought to produce a fine
grain structure and bring about many fine precipitates which play a role in strengthening the alloy through
precipitation hardening and strengthening the boundaries between grains [18] [17]. The presence of RE
elements made these qualities reliable since they enhanced the formation of Al-RE and Al-Mn-RE phases.
By adding rare earths, zirconium alloys gain resistance to heat-related changes in structure, [11] according to
[16].[17]. In aerospace and automotive areas, this quality becomes very important as materials must work in
terrible weather conditions [18].
Microstructural Refinement
The addition of RE elements to Al-Mn alloys results in significant microstructural refinement, which
contributes to their superior mechanical and thermal properties. RE elements promote the formation of fine,
uniformly distributed precipitates and inhibit the growth of coarse intermetallic phases, leading to a
homogeneous microstructure [9] Grain Refinement: RE elements act as grain refiners, reducing the grain size
and improving the mechanical properties of the alloys. For example, [22] demonstrated that mechanical
alloying of Al-Mn alloys with RE elements resulted in a fine-grained microstructure with enhanced hardness
and tensile strength.
Mechanical Alloying
In mechanical alloying (MA), powder particles are repeatedly aggregate, fractured and welded to each other.
Consequently, pure alloys are produced and their microstructures as well as personal characteristics become
distinctive. It is especially helpful in producing advanced materials, such as, nanocrystalline alloys, amorphous
alloys as well as metal matrix composites [24].
In the 1960s, Benjamin et al. came up with mechanical alloying to create oxide dispersion-strengthened (ODS)
superalloys for applications at high temperatures. Over the years, MA has been applied to make different
advanced materials, like aluminum alloys, titanium alloys and intermetallic compounds. MEA joins elements
on a molecular or atomic level when subjecting them to ball milling with intensive energy. Apart from
combining elements, this approach uses powders and ceramics which can be oxides or nitrides, to produce both
alloys and composites. In 1966, at Inco’s Paul D. Merica Research Laboratory, Benjamin and his coworkers
first explored the approach [24].. The program tried to produce oxide-dispersion strengthened (ODS)
superalloys made of nickel for use in gas turbines. Benjamin’s team used a technique called ball milling to coat
the oxide particles with nickel which served as their primary purpose in the beginning. Figure 4 illustrates the
appearance of flatter surfaces, the formation of cracks and changes in particle size during mechanical alloying.
These advantages have made MA a very useful tool for those working in materials science and engineering
[24].
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Figure 4 – Overview of mechanical alloying [25]
Mechanical Alloying Principles
The process of mechanical alloying involves repeatedly deforming, cold welding, and fracturing powder
particles in a high-energy ball mill. Mechanical energy from the milling media (balls) transfers to the powder
particles, resulting in atomic-level mixing and the formation of new phases [26].
Mechanisms for Mechanical Alloying
To begin the MA process, tiny particles are flattened and welded together to make multilayer composite
particles. During the intermediate stage, composite particles are altered more and eventually begin to break
which helps improve the microstructure and results in new phases. The last stage has the particles reach an
equilibrium when they are all the same size and have the same mixing of alloys [24].
There is a disagreement among researchers since some argue that using MA on alloys such as aluminum and
titanium is unsuitable because it may cause contamination and the appearance of unwanted intermetallic
phases. Besides, due to high power usage and slow processing, it is hard to use MA for industrial apps [21].
Common choices for mechanical alloying/milling in material science are Spex 8000, planetary mills by Fritsch
and Retsch, and Szegvari attritor. The energy is received by micro powder balls, either by shearing or by high-
speed collisions with it. The first high-energy ball mill made for mechanical alloying was made by Benjamin,
in the form of the attritor. In 1922, Szegvari came up with the attritor which soon improved how sulfur
particles are distributed during rubber vulcanization. There is a cylindrical length added to the attritor and it
holds all the powder and different-sized balls. Because of horizontal impellers on a vertical shaft, the balls and
powder are easier to move and rotate [27] , as seen in Figure 5.
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Figure 5 – High energy ball milling [27]
The impellers are organized in a progressive manner and perpendicular to one another. This design activates
the balls, reducing powder size through impact. Because of their higher capacity. Attritor mills [27] are used
for industrial purposes more than in research labs. Tumbler mills which are typical in mineral processing, can
also be used for mechanical alloying (MA) as long as their diameters are large (on the meter scale) and they
work in either the high energy impact mode or the low energy shear mode [28] .Unlike other mills, this one
can modify the speed and frequency of impacts independently, keeping the machine’s energy usage at the right
level. Apart from the mills listed before, other options are available. There are situations where mechanical
alloying is created by both rolling and ball mill processes [29].
Types of High-Energy Ball Milling mechanisms
The HEBM process incorporates a number of mechanisms, including: Head-on Impact: A direct impact
between the milling ball with the powder particles. And Joining the Impact: Using numerous strikes to
accomplish successful alloying. Multi-Ball Impact refers to the simultaneous collision of multiple milling balls
with powder particles. These mechanisms are crucial to defining the efficiency and effectiveness of the milling
process [24].
Head on impact
Such collisions make a significant impact on how the powder is structured. During an impact, the local
compression leads to the production of small grains and evenly spread alloying elements. Impacting the
milling ball directly against particles makes the materials stronger and harder [9] With this collision, the big
forces lead the powder to form distortions, connect and break in different parts. These frequent head-on
collisions improve the microstructure and add new components to aluminum [26] [9] looked at the effects of
head-on impacts on the elimination of Mn and Al-Mn complexes in aluminum. The analysis indicated that
continuous head-on impacts brought about a fine microstructure with uniformly spread precipitates which led
to much better mechanical qualities in the alloy.
Joining the Impact
Combining numerous impacts boosts the impact and enables proper alloying. Steel made using this process
involves repeatedly shaping, combining and breaking down the powder which results in fine microstructures of
homogenous alloy [24] The impact helps enhance the process of making steel by alloying. Because of many
impacts, diffusion and the formation of new phases are enhanced in the material. After studying Al-Mn-Cu-Zr
alloys mixed and processed this way, researchers found new improvements in material mechanical
characteristics and thermal stability [9]. It was observed that mixing various impacts increased the alloy’s
uniformity, improved its microstructure and increased its mechanical properties.
Multi-Ball Impact
Multi-ball impact is the simultaneous contact of many milling balls with powder particles. This type of
collision causes significant local stresses, which promotes powder particle deformation, cold welding, and
fracture. Repeated multi-ball impacts polish the microstructure and generate new phases [24] Multiball impacts
have a major impact on the microstructure of milled powders. Figure 6 shows the impact between the milling
ball with the powder particles of different mechanisms of mechanical alloying The high local stresses created
by the impact encourage the production of fine grains and the homogeneous dispersion of alloying elements.
This produces materials with higher mechanical qualities like hardness and tensile strength [9] Optimizing the
milling parameters, such as ball-to-powder ratio, milling speed, and milling time, is critical for improving the
efficiency and scalability of the high-energy ball milling process. Advanced modeling and simulation
techniques can be used to predict the optimal milling parameters for specific alloy systems [24].
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Figure 6 – Mechanisms of mechanical alloying (a) head on impact (b) joining the impact (c) multi ball impact
[30]
Techniques of Mechanical Alloying
High-energy ball milling is the most common technique used for mechanical alloying. It involves the use of a
high-energy ball mill, which generates intense mechanical forces through the collision of milling balls. The
process parameters, such as ball-to-powder ratio, milling speed, and milling time, significantly influence the
microstructure and properties of the final product [24].
High-energy ball milling (HEBM) is a mechanical alloying technique in which milling balls repeatedly collide
with powder particles. As illustrated in Figure 7 below the technique is distinguished by a high energy input,
which results in microstructure refinement, metastable phase development, and the synthesis of advanced
materials including nanocrystalline alloys and metal matrix composites [24].
Figure 7 – High energy ball milling technique [24]
Planetary Ball Milling
Planetary ball milling is a type of high-energy ball milling that makes use of a planetary ball mill. Figure 8
illustrates different types of ball milling Planetary ball milling has a larger energy input and more uniform
milling than traditional ball milling, making it suited for manufacturing nanocrystalline and amorphous alloys
[9].
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Figure 8 – Types of ball milling [31]
Attrition milling
Attrition milling is another way of mechanical alloying. It makes use of a spinning drum filled with milling
balls and powder particles. The technology offers little energy input and longer milling durations, making it
suitable for creating fine powders with controlled particle size distributions [24].
Mechanical Alloying Process
Powder Preparation
The MA process begins with the preparation of the powder mixture. The powder particles are typically blended
in a predetermined ratio to achieve the desired alloy composition. The use of high-purity powders is essential
to minimize contamination and ensure the formation of homogeneous alloys [26].
Milling Parameters
The way the mill is set up, for example, ball-to-powder ratio, milling speed and milling time, is essential for
the final looks and quality of the product. If the ball-to-powder ratio is large and the milling speed is high, the
alloying process may be accelerated, but this could also cause a lot of impurities and clusters. Having a large
portion of powder can help go through the metal faster, however, it may increase the chance for contamination
and clumping of particles. If there is not enough powder compared to the amount of ball in a mix, the
aluminum alloy may not be completely formed and it could contain uneven microstructures [24].Faster milling
speeds contribute to a rise in the energy needed and increase the speed of combination between base materials
and alloying elements. Elevated milling speed increases the speed of the alloying process; however, it may also
cause the part to get too hot and be contaminated. Conversely, when the milling speed is slow, not all the
alloying occurs and the structure is not uniform.
How long the milling process runs is also very important. Milling for a long period can cause parts of the
product to become both nanocrystalline and amorphous, though it can easily lead to contamination and the
formation of larger particles. If milling does not last long enough, the alloying may be imperfect and the
structure inhomogeneous [24].
Milling balls give energy to the powder which changes the handling of alloying and other phase changes in
MA/MM. Many factors play a part in the process of energy transfer, for instance, the mill’s special features,
how fast milling happens, the size and type of balls, the amount of powder versus balls, how full the vial is, if
grinding is done in water or air, the temperature during grinding, the air and temperature inside the mill and the
time spent milling. Using faster milling speeds or heavier balls leads to a rise in the kinetic energy of the balls
and tungsten carbide stones show the best results among them. It has been found by several researchers [32] .
[33] that a faster milling process can actually widen the range of materials known as glass formers. [34] found
that the level of NiAl produced and its tendency toward disordering go up as the MA process becomes more
intense. Other studies found out that the speed of titanium carbide (TiC) formation during mechanical alloying
(MA) increases by a large amount with each tiny adjustment in milling ball density [35].
The choice of ball size, the way balls are dispersed and their overall number should help achieve the most
efficient usage of the vial. A big collection of balls close together reduces the distance between collisions,
though looser packing reduces how often the balls hit. It is common to use ball/powder weight ratios from 5:1
to 10:1 and the results suggest they work very well.
In high energy ball milling, powder grains tend to vibrate together and generate cracks. How strongly and
where the material fractures is affected by its ability to deform and the temperature at which it is milled. This
means that the milling process’s major phase transition events are mainly affected by the temperature used in
milling. [36] studied the effects of combining silver and copper into an alloy. Mixing the systems together
gives off heat. It was found through the study that solid solutions stay intact at low milling temperatures, but
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higher temperatures lead to their breakdown. While the balls are rotating during milling, some of their energy
turns into heat which makes the powder get warmer.
In MA, powder particles are welded together and then fractured repeatedly while colliding inside the balls in a
mill. How strong or tough the powder particles are greatly affect’s the actions that happen during welding and
when the material breaks. Consequently,
Ductile/ductile systems
Many alloyed elemental mixes belong in this group, since is the first to describe the process. . [37] Later,
Benjamin wrote additional papers to give a deeper analysis of this subject. Through optical microscopy, the
MA process can be simply divided into five parts which these results confirm. Figure 9 illustrates What
happens when a ball collides with powder.
Figure 9 – Events that occur during the ball-to-powder impact [25]
This figure demonstrates the way the powder particles get trapped among two balls impacting each other. From
the beginning, micro forging deforms equiaxed ductile particles into a flat and flaky form. Milling at lower
temperatures causes a sandwich-like structure and also makes the particle size larger. The third stage of the
process. Fracturing may occur more often in this step as strain hardening makes particles tougher and more
likely to break. During random welding orientation, several groups of lamellar colonies are created inside the
particle and these groups have no fixed orientation. When equilibrium is reached, the material’s hardness and
particle size end up at their maximum values which means there is balance in how fast the material welds
together and breaks down. After five cycles of mechanical alloying (MA), lamellar structures in the particles
are so small that they become invisible under an optical microscope. In alloying, the initial phase is diffusion
which happens during or at the final phase of the third stage. It is possible because carbon and silicon develop
fine repeating bands made up of each element. Furthermore, milling at elevated temperatures and having
defects caused by deformation makes it easier for alloying elements to move in the material. During the fifth
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step of the MA process, the alloying procedure is achieved. Examples of ductile/ductile systems are Ni-Cr, Cu-
Ni, Cu-Zn and Ni-AI. Choosing a stoichiometric mix resulted in synthesizing Nb3Sn [38].a superconducting
compound, owing to the addition of MA of Nb and Sn in this categorization. Making Mn Bi through
mechanical alloying of manganese (Mn) and bismuth (Bi) is another way that falls into this group as well [39].
Ductile/brittle systems
In the beginning, Benjamin and his group proved that some ODS alloys were ductile/brittle with their research.
Oxide particles are spread evenly along with the ductile phase, while the separate layers of the steel join
together.[40].
Brittle/brittle systems.
At the beginning, experts thought that brittle-to-brittle milling would result in the particles breaking and no
alloying would happen. In fact, it is clear that the alloying process works well with the Si-Ge system using
powder milling [40]. A number of NiZr2 and Ni11,2Zr9 intermetallic compounds were milled to produce
amorphous alloys [40], [41]. These cases demonstrate that using alloys and transferring materials is possible
during high energy ball milling of brittle/brittle materials. Even so, there is a lack of clear knowledge about
how these alloying mechanisms work. Granular systems that underwent mechanical alloying were found to
display microstructure characteristics that set them apart from lamellar types, mainly those that behave in a
ductile way. It is believed that the transfer of material happens because of diffusion during the temperature rise
that happens during milling.
Morphological evolution during mechanical alloying
The impact of mechanical alloying on ductile powders was explored [40] [42] . It was found in their
investigation that the process involves some key steps, as presented in Figure 10. At first, it is important to mix
and fuse the powder particles. First, deformation and welding resulted in flake particles with layers of alloy
materials mixed together. While powder particles are being welded, the number of particles reduces as the size
of the particles increases. In addition, subjecting the particles to mechanical alloying caused a lot of plastic
deformation which made their hardness increase a lot. the process. A model was proposed [43] [44] [45] after
researching the stages of particle Afterward, fine-grained particles called equiaxed started to form and the
clumping of layered particles resulted in irregular particle direction. At the same time, particle size is less
which forms a complex pattern like marble. Because particles are getting harder and less ductile, there is a
higher probability that they will break. However, it is during the last step of mechanical alloying that each
particle arrives at the overall composition and hardness. Besides the aforementioned reasons, 37 equilibrium
maintains the fracture-welding process at a steady level which ensures the mean particle size is almost
unchanged at the very end of formation by milling and this model described A and B type particles coming
together.
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Figure 11 –. The different stages of mechanical alloying in ductile-brittle system [46]
Relevant Investigations on Mechanical Alloying for Aluminum Alloys
The study [15] looked at how Al-Mn-Cu-Zr alloys were formed and what characteristics they possessed as a
result of mechanical alloying. It was found in the study that ball milling at high power and then sintering with
heat led to a finer microstructure and enhanced hardness and tensile strength. Thanks to the RE elements, these
alloys formed strong intermetallic complexes which raised their strengths. [15] They found that including Zr
into the alloy increased its hardness and tensile strength. As the aluminum alloys aged, small particles known
as precipitates formed and made the properties listed above even better Sc and Zr in the alloys raised the
alloys’ ability to stand up to temperatures and avoid softening, making them fit for high-temperature processes.
Hot press sintering (HPS)
HPS stands for hot press sintering and it helps produce solid and robust materials. It is a great way to
consolidate mechanically alloyed powder thanks to the refined grains and smaller numbers of pores it brings.
In Figure 11, the hot press sintering process is clearly presented and it is majorly applied to create sophisticated
materials such as aluminum alloys, titanium alloys and metal matrix composites [47] [48].
Figure 11 – Schematic setup for hot press sintering [49]
Historical Development
In the early 20th century, hot press sintering was developed to produce dense ceramic materials. Since then, it
has been adapted to produce metallic materials with complex compositions and microstructures.
Advancements in sintering equipment and process control systems have expanded HPS's applications in
materials science and engineering [47] Hot Press Sintering (HPS) is a valuable tool for producing advanced
materials with high density, fine grain size, and superior mechanical properties. It is especially useful in high-
temperature and high-stress applications [48].
Process Parameters of Hot Press Sintering
The sintering temperature plays an essential role in HPS due to its impact on densification and microstructure
of the final product. At high sintering temperatures, atoms diffuse and make strong interparticle bonding,
leading to a high-density product. Nevertheless, high sintering temperatures may cause a grain coarsening and
mechanical properties deterioration [47].
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The sintering pressure is another critical parameter in HPS, as it influences the mechanical properties of the
end product. High sintering pressures promote the consolidation of powder particles and the formation of
dense, high-strength materials. However, excessive sintering pressures can lead to cracking and deformation,
particularly in materials with complex shapes [48].
The holding time refers to how long the material remains at the sintering temperature and pressure. The
holding period affects the degree of densification and the development of interparticle connections. [47] The
heating rate is the pace at which the material reaches the sintering temperature. The heating rate effects the
final product's microstructure and characteristics. High heating rates can cause thermal gradients and uneven
densification, whilst low heating rates can result in excessive grain growth [48].
Impact of Hot Press Sintering on Al-Mn-RE Alloys
Hot press sintering promotes the refinement of the microstructure in Al-Mn-RE alloys, resulting in fine grain
size and uniform distribution of precipitates. [50] The mechanical properties of Al-Mn-RE alloys are
significantly influenced by the HPS process parameters. High sintering temperatures and pressures promote the
formation of strong interparticle bonds and fine-grained microstructures, resulting in materials with superior
mechanical properties. However, excessive sintering temperatures and pressures can lead to grain coarsening
and degradation of mechanical properties [50].
The thermal stability of Al-Mn-RE alloys is enhanced by the HPS process, as the fine-grained microstructure
and uniform distribution of precipitates inhibit grain growth and recrystallization at elevated temperatures.
This makes HPS-processed Al-Mn-RE alloys suitable for high-temperature applications, such as aerospace
components and automotive engine parts [50].
Mechanical alloying is carried out under heavy plastic deformation of powder particles.[51] provided TEM
evidence to be this hypothesis, in their study, showing the existence of shear bands due to the formation of
non-uniform deformation induced during high-energy ball milling. Again, a research team carried out a study
that confirmed that extreme plastic work can cause isolated phases within several Nanocrystalline alloys [46]
[52] [53].
Grain boundary strengthening
It was found in 1950s by Hall and Petch that steel gets stronger when the grain size gets smaller. Working on
their essential dislocation theory, they introduced the Hall-Petch connection related to dislocations building up
next to each other. Still, this model may not be appropriate for grain sizes that are less than 100 nm. The Hall-
Petch coefficient is not constant; sometimes, certain nanocrystalline alloys show lower yield strength thanks to
the inverse Hall effect.[55] [56].
Solid solution strengthening
Adding more solutes amounts to concentrating the solution. That aside, there is general agreement that the
addition of MA tremendously increases the ability of solids to dissolve. Therefore, the strength of MA alloys is
expected to undergo a significant upgrade. Researching on nanocrystalline Al-Mn alloy [57].
Precipitate Analysis in Al-Mn-RE Alloys
Introduction to Precipitate Analysis in Al-Mn-RE Alloys Precipitate analysis is a critical aspect of materials
science, particularly in the study of aluminum alloys. Precipitates are secondary phases that form during the
solidification or heat treatment of alloys, and they play a significant role in determining the mechanical
properties, thermal stability, and corrosion resistance of the material. In Al-Mn-RE (aluminum-manganese-rare
earth) alloys, precipitates such as Al-Mn, Al-RE, and Al-Mn-RE intermetallic compounds are key to enhancing
strength, hardness, and high-temperature performance [58].
Precipitates in Al-Mn-RE alloys contribute to strengthening mechanisms such as precipitation hardening, grain
boundary strengthening, and dispersion strengthening. The formation of fine, uniformly distributed precipitates
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during aging or sintering significantly improves the mechanical properties of the alloy, including hardness,
tensile strength, and fatigue resistance) [50].
Rare earth elements such as lanthanum (La), cerium (Ce), and neodymium (Nd) are known to refine the
microstructure of aluminum alloys and promote the formation of stable precipitates. [59].Manganese is a key
alloying element in Al-Mn-RE alloys, as it forms stable intermetallic compounds such as Al6Mn and Al12Mn.
These precipitates contribute to strengthening mechanisms and improve the thermal stability of the alloy [12].
Rare earth elements promote the formation of fine, thermally stable precipitates such as Al-RE and Al-Mn-RE
compounds. These precipitates inhibit grain growth and recrystallization, enhancing the mechanical properties
and thermal stability of the alloy [60].
Annealing in Al-Mn-RE Alloys
Annealing is a heat process whereby a metal is heated to a specific temperature and allowed to cool slowly.
This softens the metal which means it can be cut and shaped more easily [60] Mechanical properties (hardness,
microhardness, and density) of Al-Mn-RE alloys are optimized due to annealing. The mechanism is beneficial
to generate fine, homogeneously distributed precipitates, which can strengthen the precipitation hardening and
grain boundary strengthening mechanisms [50].
Microstructure of Al-Mn-Zr-RE Alloys
The grain refining effect of Al-Mn alloys can be further enhanced by Zr, Ce and Y addition, and the refinement
of grains was obtained in finer and superior mechanical properties were achieved., the fine grains inhibit the
motion of dislocations and improve the alloying strength and hardness [50]. At elevated temperatures, these
precipitates act as obstacles to the motion of the dislocations, resulting in grain refinement [11] The phase
transformation in Al-Mn-Zr-Ce-Y alloys is controlled by the alloy composition and heat treatment processes. It
can be seen that the addition of Zr, Ce, and Y strengthens the formation of the stable intermetallic compounds
improving the thermal and mechanical properties of the alloy [23].
Al-Mn-Zr-Ce-Y alloys' hardness and tensile strength are greatly increased by the production of fine grains and
uniformly dispersed precipitates. For example, [50] found that high-energy ball milling followed by hot-press
sintering produced a fine-grained microstructure with high hardness and tensile strength. The homogeneous
distribution of precipitates in Al-Mn-Zr-Ce-Y alloys enhances fatigue resistance by preventing crack formation
and propagation. This makes the alloys appropriate for cyclic loading applications such as aerospace
components and automobile engine parts [16].and the inclusion of Zr, Ce, and Y increases creep resistance in
Al-Mn alloys by generating thermally stable precipitates that prevent grain development and dislocation
motion at high temperatures. This makes the alloys appropriate for high-temperature applications like jet
engines and exhaust systems [11].
METHODOLOGY
This study focused on the process flow of the Al-Mn-Zr-RE alloys, including initial alloy melting and casting,
mechanical alloying, and compaction by hot press sintering, followed by characterization. Its approach was to
obtain a homogeneous distribution of alloying elements by controlling microstructure and phase stability and
demanding mechanical stability at high temperatures. The rare earth (RE) elements used, which are zirconium
(Zr), yttrium (Y), and cerium (Ce) were selected based on their established abilities to refine microstructure,
increase recrystallization resistance, and stabilize thermally favorable phases [4].
Materials
Raw Materials
The starting materials used are the Al-10 wt%Mn, Al-20 wt% Ce, Al-9wt%Y master alloys and commercially
pure Zr (99,9%). As illustrated in the Table 1 below.
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Table 1 – The composition of the studied alloys, at. %
Sample Mn Zr Y Ce
Al-Mn-Zr 4.0 1.2 – –
Al-Mn-Zr-Y 4.0 1.2 0.6 –
Al-Mn-Zr-Ce 4.0 1.2 – 0.6
Mechanical Alloying Process
Shear-induced solid-state reactions at small deformations during mechanical alloying (MA) are an integral part
of this work with the objectives being to control microstructure, homogeneously segregate RE elements, and
stimulate the formation of a hardening phase of interest. The master alloys and Zr were crushed and ground
into chips prior to mechanical alloying.
Selection of Mechanical Alloying Equipment
Planetary Ball Mill
Because of its high energy impact mechanism and excellent efficiency for homogenous mixing and alloying a
planetary ball mill was selected. Such jars can rotate both on their own axes and around the common axis,
which promotes effective energy transfer upon collision, allowing effective powder particles repeat fracturing
and cold welding.
Milling Chamber with Balls
Stainless steel jars were selected for their durability and compatibility Hardened steel balls (10 mm diameter)
were used to maximize energy transfer. Airtight jars with a capacity of 500 ml provide an inert argon
atmosphere for milling. The following parameters were adopted after preliminary testing and literature
benchmarking [61] Milling speed: 300 rpm. The Ball-to-Powder Ratio (BPR) is 20:1 by weight, optimized for
fine, homogeneous powders without excessive cold welding. Milling time is 20 hours, with cooling breaks
every 2 hours to avoid overheating. To prevent powder agglomeration and cold welding, use ~1 wt.% stearic
acid as a process control agent Milling was carried out under high-purity argon to prevent oxidation.
Temperature Monitoring
A thermocouple incorporated in the milling chamber enabled real-time temperature monitoring. Milling
temperatures were controlled below 70 °C using intermittent milling and active air cooling. To prevent
oxidation, the powders were collected in an argon-filled glove box. The powder had a delicate, flaky
morphology that is typical of ductile metal alloys subjected to MA.
The Hot Press Sintering Process
After mechanical alloying, the powder samples were compressed using hot press sintering (HPS) to form dense
billets.
Equipment Used
The hydraulic hot press features a heating chamber and a vacuum/inert gas system. The die set has a 20 mm
inner diameter and is lined with graphite foil to prevent powder adhesion. Thermocouples near the sample
allow for precise temperature monitoring.
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Sintering Conditions
Two sintering temperatures, 350 °C and 450 °C, were employed. Holding times of 15 minutes,30
minutes,1hour, and 2 hours were examined. Uniaxial pressure of 50 MPa was applied during the holding step.
High-purity argon gas was continuously flushed into the chamber. The sintered compacts were then cooled in
the same controlled environment to room temperature before being extracted for analysis.
Characterization of Al-Mn-Zr-RE. Alloys
The sintered samples were thoroughly characterized to determine their microstructure, phase composition,
thermal stability, and mechanical properties. The techniques used are scanning electron microscopy (SEM), X-
ray diffraction (XRD), Vickers microhardness testing, and density analysis. Scanning Electron Microscopy
(SEM) was utilized to analyze the morphology, grain boundaries, and distribution of intermetallic particles in
sintered alloys. Preparation: Samples were sectioned, mounted, polished with diamond paste (to 0.05 µm), and
etched with Keller's reagent (2 mL HF, 3 mL HCl, 5 mL HNO₃, 190 mL H₂O). Observation Mode: High
vacuum with 15-20 kV of accelerating voltage. Magnification ranges from 500x to 10,000x for detailed
microstructural analysis. Image analysis software was used to assess particle size distribution and grain
refinement with RE additions. The presence of polished grains and uniformly distributed precipitates suggested
increased heat stability and dispersion strength.
Phase Composition Analysis Using X-Ray Diffraction (XRD)
XRD was used to detect crystalline phases and assess lattice parameter changes caused by mechanical alloying
and sintering. Instrument: PANalytical X'Pert PRO X-ray diffractometer. • Radiation source is Cu-Kα (λ =
1.5406 Å). • Scanning range is 20° to 90° 2θ. • Step size: 0.02°, scanning rate: 1°/min. The HighScore Plus
software identifies phases using the ICDD PDF-4+ database. XRD patterns revealed the presence of primary
Al matrix and intermetallic phases such as Al₁₁Mn₄, Al₃Zr, Al₈Ce, and Al₃Y. Peak broadening and shifts were
also used to determine crystallite sizes and lattice strains, consistent with Williamson-Hall analysis [24].
Hardness tests
Microhardness tests were used to quantify the mechanical strength gains from alloying and annealing
procedures. Instrument: LECO LM247AT microhardness tester. Test load is 100 g (HV0.1). Figure 12
illustrates hardness tester machines in MISIS laboratory Dwell time: 15 seconds. Measurements: Averaged
five readings per sample. Sample conditions: Measurements were obtained before annealing and after heat
treatments of 15 minutes, 30 minutes, 1 hour, and 2 hours at 350°C and 450°C. The hardness values increased
significantly as the annealing time and temperature increased. At 450 °C for 2 hours, the Al-Mn-Zr alloy
achieved the maximum microhardness (440 HV) due to Al₃Zr precipitation and grain refining.
Figure 12 – Microhardness tester in MISIS laboratory
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Density Measurements.
The Archimedes' principle was utilized to determine the density of sintered samples. Medium: distilled water
was used.
Statistical Analysis and Error Considerations
To confirm that the results were reproducible and reliable, all measurements were repeated several times under
identical conditions. Microhardness testing was conducted at five sites for each sample. The mean and standard
deviation were reported. Outliers exceeding ±10 % were deleted. • Archimedes' density tests were done three
times for each sample. Variability was ±0.01 g/cm³. Cross-validation of peak intensities and positions was
performed using conventional PDF cards during phase analysis. Errors in peak broadening measurements were
assessed based on instrument resolution, and data were adjusted using a silicon reference.
Data Processing Tools
Microsoft Excel, OriginPro 2023, and Minitab were used for data plotting, statistical treatment, and regression
modeling where applicable.
ANOVA (Analysis of Variance) was applied to compare the effects of annealing time and temperature on
hardness and density values. A p-value < 0.05 was considered statistically significant.
Waste Disposal
Metal waste and unused powders were collected in designated recycling bins.
Chemical wastes, such as spent stearic acid, were disposed of in accordance with institutional and
environmental requirements.
Safety and Environmental Considerations
All synthesis and characterization operations followed safety and environmental protocols Powders were
handled in a fume hood to prevent inhalation risks. Always we wear nitrile gloves and anti-static lab coats. We
Store stearic acid in sealed containers due to its flammability in powdered form. Argon was utilized for
melting, mechanical alloying, and sintering to reduce oxidation and fire dangers.
Pressure valves, leak detection systems, and flow regulators ensured safe handling of gas cylinders. Furnace
and Hot-Pressing Safety Operators adhered to thermal PPE requirements, including insulated gloves and face
shields. • Emergency power cutoff and fire suppression systems were installed near furnace areas. Waste
Disposal Metal waste and unused powders were collected in designated recycling bins. And Chemical wastes,
such as spent stearic acid, were disposed of in accordance with institutional and environmental requirements.
Methodological Workflow Summary
The entire experimental methodology is summarized in Figure 13 in the flowchart below illustrating each key
stage in sequence:
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Figure 13 – Methodological summaryResults and discussion
Powder Particles Analysis
Figure 14 shows granular morphology of the alloys from SEM and TEM the powders showed a uniform
particle size distribution.
Figure 14 – Granular morphology of of (a) Al-Mn-Zr from TEM (b) Al-Mn-Zr from SEM c) Al-Mn-Zr-Y from
TEM (d) Al-Mn-Zr-Y from SEM (e) Al-Mn-Zr-Ce from TEM and f) Al-Mn-Zr-Ce
Initially, large and irregular particles were observed, but they progressively became refined due to repeated
fracturing and welding. By 10 hours of milling, the morphology was flake-like for Al-Mn-Zr and more
equiaxed for Al-Mn-Zr-Y and Al-Mn-Zr-Ce, which indicates better powder flowability and compact ability for
the RE-doped alloys. Based on what is shown in Figure 15, the number of small granules increased over time,
proving the process of fragmentation during mechanical alloying.
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Figure 15 – Powder particle size for the alloys studied
X-ray diffraction (XRD) analysis
X-ray diffraction (XRD) was employed to analyze the crystalline phases present in the milled for 10 hours and
compacted samples revealed distinct structural evolutions induced by the addition of rare earth elements (Ce
and Y). Crystallite sizes calculated using the W-H equation indicate that the presence of RE elements
influenced grain refinement, with smaller grain sizes generally correlating to higher peak broadening the lattice
parameters varied widely between the three compositions. The lattice parameters were calculated assuming
100% solubility of each alloying element as determined using Vegard's law. The analysis of the crystallite size
and lattice parameter indicated that there were remarkable differences between the Al-4Mn-1,2Zr base alloy
and its Ce- and Y-modified variants, especially between various processing conditions. The grain sizes of
milled samples were constantly the smallest, and the Al-4Mn-1,2Zr-0.5Y alloy had the smallest crystallite size
(~16 nm), followed by Al-4Mn-1,2Zr-0,6Ce (~18nm) and Al-4Mn-1,2Zr (~20nm). Compaction produced a
large grain growth, particularly at 450°C where crystallite sizes of up to ~84 nm in Ce- and ~81 nm in Y-
containing alloys were achieved. This increase is indicative of thermal recovery and recrystallization processes
which occur because of the high temperature of compaction. Conversely, the samples compacted at 350°C
proved to have smaller grains indicating low atomic mobility.
There were also variations in lattice parameters. Phase stability was confirmed by the fact that most compacted
samples (including those containing Y) were very near the FCC Al value (0.404 nm). There are however some
anomalies including higher lattice parameters in Al-4Mn-1,2Zr compacted at 450°C (0.54 nm) and Al-4Mn-
1,2Zr-0,6Ce compacted at 350°C (0.50 nm) which indicate possibility of internal strain or solute segregation.
Conversely, the Y-modified alloy showed no variation in the lattice parameters in all the states (~0.4045–
0.4047 nm), suggesting a higher solute solubility or less distortion.
These results affirm that milling causes extensive grain refinement, whereas thermal compaction, particularly
at 450 oC causes grain coarsening, with Ce and Y having different effects on the magnitude of crystallite
growth and lattice stability. This microstructure-thermal processing balance is important to maximize the
mechanical properties in these enhanced aluminum alloys. The results are shown in Table 2 below.
Table 2 – Crystallite size and lattice parameters for the alloys-studied
Alloy Crystallite size, nm aavg, nm aT (theoretical)
Al-4Mn-1,2Zr milled 20 ± 2 0.4039 ± 0.0001 0.4045
Al-4Mn-1,2Zr compacted 350 25 ± 8 0.4047 ± 0.0001 –
Al-4Mn-1,2Zr compacted 450 59 ± 7 0.4054 ± 0.0001 –
Al-4Mn-1,2Zr-0,6Ce milled 18 ± 4 0.4041 ± 0.0001 0.4046
Al-4Mn-1,2Zr-0,6Ce compacted 350 40 ± 9 0.4050 ± 0.0001 –
AlMnZr AlMnZrCe AlMnzrY
0
20
40
60
80
100
120
M
e
a
n
p
o
w
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e
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,
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Al-4Mn-1,2Zr-0,6Ce compacted 450 84 ± 7 0.4051 ± 0.0001 –
Al-4Mn-1,2Zr-0.5Y milled 16 ± 2 0.4036 ± 0.0001 0.4041
Al-4Mn-1,2Zr-0.5Y compacted 350 46 ± 5 0.4045 ± 0.0001 –
Al-4Mn-1,2Zr-0.5Y compacted 450 81 ± 10 0.4047 ± 0.0001 –
The XRD patterns of the 10-hour mechanically milled powders in the Figure 16 below reveal considerable
peak broadening and a decrease in peak intensity, indicating nanocrystalline structures and lattice strain caused
by high-energy ball milling. All three alloys show α-Al (FCC) as the dominant phase, with characteristic peaks
at 2θ values of ~38°, 44°, 65°, and 78°, corresponding to (111), (200), (220), and (311) planes, respectively.
Al-4Mn-1,2Zr (Base Alloy) consists primarily of α-Al with traces of intermetallic such as Al₃Zr. Al₆Mn,
Al₄Mn. Peak broadening suggests reduced crystallite size (≈20–30 nm estimated via W-H equation).
Figure 16 – XRD representation of alloys milled alloys
Microhardness of powder particles
Microhardness measurements were performed after sintering the mechanically alloyed Al-Mn-Zr and Al-Mn-
Zr-RE (Y and Ce) alloys under varied HPS circumstances to evaluate their mechanical behavior. The
parameters evaluated were HPS temperature of (350 and 450), annealing temperature (350, 400, and 450 °C),
and duration (up to 4 hours). The initial powder values for the alloys are illustrated in the Table 3 below the
effect of these characteristics on hardness is examined independently for each alloy system.
Tabel 3 – Initial powder particles micro hardness values
Alloy Microhardness (HV)
Al-Mn-Zr 265 ± 8
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Al-Mn-Zr-Y 240 ± 5
Al-Mn-Zr-Ce 230 ± 4
Analysis of the sintered alloys
Density of the Sintered Alloys
Figure 17 illustrates Density values for the alloys after sintering at 350 and 450 °C
Figure 17 – Density values for the alloys after sintering at 350 and 450 °C
Densities of the alloy were measured before and after annealing of the sintered samples. After 2 hours of
annealing at 450 °C, the Al-Mn-Zr alloy's density increased from 2.85 to 2.87 g/cm³, indicating pore removal.
Similarly, Al-Mn-Zr-Y increased from 2.87 to 2.89 g/cm³, showing enhanced densification after annealing.
XRD for sintered alloys
The XRD patterns of the compressed and sintered alloys as illustrated in Figure 18 below it reveals significant
microstructural change post-milling. Heat treatment between 350 °C and 450 °C promotes recovery and
recrystallization with growth of the crystallite size, the development of intermetallic phases, and lattice strain
relaxation. Al-4Mn-1,2Zr shows clearer and sharper α-Al peaks, indicating grain growth and stress release.
Stable Al₃Zr and Al₆Mn phases were observed, suggesting diffusion-controlled precipitation.
Zr_350 Zr_450 ZrY_350 ZrY_450 ZrCe_350 ZrCe_450
2.80
2.85
2.90
D
e
n
s
it
y
,
g
/s
m
3
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.
Figure 18 –XRD representation of alloys compacted at 350 °C (a) and 450 °C (b)
The XRD patterns of the Al-Mn-Zr-RE alloys sintered at 350 and 450 °C indicate that FCC-Al matrix is
present in all the samples with intermetallic compounds Al3Zr, Al3Y and Al11Ce3 formed. Peak broadening at
350 °C was higher and secondary peaks intensity was smaller indicating nanocrystalline and strained structures
were developed with incomplete phase precipitation. Conversely, 450°C pressing raises the crystallinity and
sharpens intermetallic peaks, which means better phase development and less lattice strain. These findings
clearly show that, higher compaction pressures enhance the degree of phase formation completeness and
stabilization of intermetallic dispersion, which are pivotal to mechanical performance and thermal stability of
these advanced aluminum alloys.
The stability of these phases post-annealing, especially after 2 and 4 hours, supports the structural integrity of
the alloy system under thermal exposure. XRD analysis revealed the formation of various intermetallic phases
during mechanical alloying and hot pressing. The key diffraction peaks identified as α-Al, Al₆Mn, and Al₃Zr
phases. Samples with Ce and Y exhibited extra peaks for Al₁₁Ce₃ and Al₃Y phases.
Microhardness of sintered sample
The Al-Mn-Zr alloy sample consolidated at 450 and annealed at 400 °C (450HPS@400) had the highest
microhardness across all circumstances tested. This is due to the synergistic effect of high compaction pressure
and enough heat activation, which promotes improved atomic diffusion, densification, and the creation of a
uniform ultrafine-grained structure. These results are consistent with [37] [24] findings on densification
behavior and diffusion-enhanced sintering in mechanically alloyed Al-based systems. The 350HPS@350 °C
condition exhibited the second highest hardness. Despite the lower compaction pressure, the lower sintering
temperature aided in maintaining a refined microstructure with minimal grain coarsening. The
350HPS@450 °C sample had the lowest measured hardness. This is most likely due to rapid grain
development and probable partial recrystallization at high temperatures, as reported by [20] which reduce
dislocation density and hardness. These results show that for Al-Mn-Zr, intermediate temperature (400 °C)
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with high sintering at (450°C) provides the best compromise between densification and microstructural
refinement.
The Al-Mn-Zr-Y alloy originally exhibited maximum hardness at 450HPS@400 °C, but decreased after 2
hours of sintering. This can be attributable to grain coarsening and a drop in dislocation density caused by
recovery processes. Yttrium, a rare earth metal, works as a powerful grain boundary stabilizer and refiner,
although extended exposure to high temperatures can reduce its effectiveness [62].The 350HPS@350 °C
condition had the second highest hardness, with values comparable to the 450HPS@400 °C. This result
supports the findings of [43]who emphasize the importance of controlled thermal exposure for maximizing
hardness in mechanically alloyed systems. The 350HPS@450 °C sample had the lowest hardness, indicating
the negative impact of high temperature at low compaction pressure, potentially due to inadequate
consolidation and excessive grain growth.
In the Al-Mn-Zr-Ce system, 350HPS@350 °C produced the maximum hardness, followed by
350HPS@400 °C and 450HPS@400 °C. Interestingly, the lowest hardness was achieved at 350HPS@450 °I.
This pattern indicates that Ce operates differently than Y, possibly due to differences in atomic size, diffusion
properties, and compound formation tendency. Cerium forms stable intermetallic, such as Al₁₁Ce₃, which
contribute to hardness when well-dispersed and nanosized. However, high sintering temperature or duration
may cause coarsening and phase segregation, limiting the strengthening effect, as shown by [63].Moreover,
low pressure combined with low-to-moderate temperatures appeared optimal in preserving the fine
microstructure, indicating that Ce-containing alloys benefit more from gentler sintering conditions.
Comparative Analysis and Interpretation
A comparative summary of the hardness trends across the three alloy systems under varying HPS conditions is
provided in the Figure 19 below:
a
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
200
250
300
350
400
AlMnZrY_350+350
AlMnZrY_350+450
AlMnZrY_350+400
AlMnZrY_450+400
HV0.05
t, h
350HPS+450
350HPS+400
350HPS+350
450HPS+400
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b
c
Figure 19 – Micro hardness values at different temperature of (a) Al-Mn-Zr b) Al-Mn-Zr-Y and (c) Al-Mn-Zr-
Ce
The Al-Mn-Zr-Ce alloy showed moderate improvement, from an initial microhardness of 250 HV to 340 HV
after 2 hours of annealing, with a corresponding macro hardness increase to 220 HV. As indicated in Table 4
below prolonged annealing to 4 hours resulted in a slight reduction, indicating potential over-aging effects
Table 4 –. Hardness values before and after annealing.
Alloy Condition Microhardness (HV) Hardness (HV)
Al-Mn-Zr Sintered 280 ± 15 210 ± 10
Al-Mn-Zr Annealed 2h @ 450°C 440 ± 20 400 ± 15
Al-Mn-Zr-Y Sintered 250 ± 5 200 ± 8
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
300
350
400
450
AlMnZr_350+350
AlMnZr_350+400
AlMnZr_350+450
AlMnZr_450+400
HV0.05
t, h
450HPS+400
350HPS+450
350HPS+400
350HPS+350
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
250
300
350
400
450
AlMnZrCe_350+350
AlMnZrCe_350+450
AlMnZrCe_350+400
AlMnZrCe_450+400
HV0.05
t, h
450HPS+400
350HPS+450
350HPS+400
350HPS+350
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Al-Mn-Zr-Y Annealed 2h @ 450°C 300 ± 15 230 ± 10
Al-Mn-Zr-Ce Sintered 260 ± 12 190 ± 9
Al-Mn-Zr-Ce Annealed 2h @ 450°C 345 ± 18 230 ± 10
The mechanical properties of the alloys were assessed using microhardness and hardness tests. The as-pressed
Al-Mn-Zr sample had a microhardness of 300 HV and a hardness of 210 HV, which rose dramatically after
annealing at 450 °C for 2 hours to 440 HV and 400 HV, respectively. The increased hardness is due to fine
grain strengthening and homogenous particle distribution. Al-Mn-Zr-Y samples had significantly lower
starting values (250 HV microhardness), but after annealing, the hardness increased to 400 HV (micro) and
230 HV (macro), confirming the yttrium-induced grain boundary pinning.
Hardness values significantly improved after hot pressing and annealing, especially at 450 °C. Initial
microhardness for Al-Mn-Zr, Al-Mn-Zr-Y, and Al-Mn-Zr-Ce were 279.6, 249.5, and 256.2 HV respectively.
After annealing for 2 hours Annealing at 4 hours showed a slight reduction in values, indicating thermal
softening due to over-aging or grain growth. As shown by comparison of the three alloys with their respective
hardness values
Microstructural Analysis
SEM examination employing Backscattered Electron (BSE) imaging was performed to evaluate the
microstructural evolution of Al-Mn-Zr-based alloys (with Ce, Y) subjected to Hot Press Sintering (HPS) at 350
and 450 MPa, both before and after 4 hours of annealing. The micrographs indicated significant variations in
grain shape and elemental dispersion.
350HPS Compact (Before Annealing) The microstructure consisted of tiny, somewhat agglomerated granules
scattered uniformly throughout the matrix. The EDS elemental maps in figure below showed a homogeneous
distribution of Mn, Zr, Ce, and Y, indicating effective alloying during mechanical milling (10 hours). Fe
contamination from grinding pots was minimal (~0.1-0.2%), in line with [50] findings.
350HPS Compact (After 4 Hours of Annealing After annealing, substantial grain development and smoother
interfaces were observed, as indicated in Figure 20 below indicating thermally triggered diffusion and partial
coalescence. Small Mn-rich precipitates appeared, indicating the early stages of phase segregation, as
previously observed in binary Al-Mn alloys [50]..
The higher compaction pressure resulted 450HPS Compact (Before Annealing) in a denser and more refined
structure with well-defined grain boundaries and minimal porosity. Granules remained fine, and the matrix
showed excellent cohesiveness, indicating increased densification due to greater HPS.
a
b
c
d
e
f
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Figure 20 – SEM-BSE Images of a) Al-Mn-Zr , b) Al-Mn-Zr-Ce c) Al-Mn-Zr-Y350HPS before Annealing
and d) Al-Mn-Zr e) Al-Mn-Zr-Ce f) Al-Mn-Zr-Y 350HPS after Annealing 450HPS Compact (After 4 Hours of
Annealing) Annealing increased observable coarsening and the creation of intermetallic-rich zones, as
illustrated in figure 21 below especially in Mn and Ce areas. Despite the increased particle size, the elemental
distribution remained relatively uniform. This result is consistent with the findings of [16] [15] who found that
RE additions impacted grain boundary stability and increased heat resistance.
EDS Mapping and Phase Distribution
Elemental distribution in 350 and 450 HPS alloys are shown in Figure 21.
Figure 21 – Elemental distribution in 350 and 450 HPS alloys (a)EDS Image (b) Fe; (c) Zr (d) Al (e) Mn (f)
The elemental distribution of Mn, Zr, Ce and Y is consistent across all samples. Minor Fe contamination (~0.1-
0.2 vol%) is consistent with earlier literature [20] possibly due to steel balls and vials used in high-energy
milling.
Mechanical Properties
The mechanical properties at compression tests for Al-Mn-Zr-RE alloys processed via 350 MPa and 450 MPa
HPS was evaluated at both room and elevated temperature: Table 5 below shows that the strength properties at
room and higher temperature for both 350 and 450 HPS levels.
a
b
c
d
e
f
a
b
c
d
e
f
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Table 5 – The mechanical properties after 10 hours MA and annealing for 350 ,400 and 450 temperatures
Alloy Sintering/
Annealing
Temperature (°C)
Tests at 20 °C Tests at 350 °C
σ0.2, MPa σmax, MPa ψ, % YS, MPa ψ, %
Al-4Mn-1,2Zr 350/350 639±7 695±10 1.4±0.2 290±10 7.2±0.8
350/400 585±5 641±7 1.4±0.2 265±5 11±1
350/450 567±10 639±7 1.6±0.2 237±5 12±2
450/400 766±10 881±5 2.4±2 321±10 7±2
Al-4Mn-1,2Zr-
0,6Ce
350/350 590±10 945±7 43±3 102±5 44±5
350/400 574±5 990±5 42±3 97±5 45±4
350/450 547±7 987±6 42±3 94±5 45±5
450/400 670±10 733±10 17±2 121±10 22±2
Al-4Mn-1,2Zr-
0,6Y
350/350 684±5 877±10 27±3 198±10 42±2
350/400 606±5 777±10 25±5 136±10 43±2
350/450 540±10 762±5 25±5 132±10 44±2
450/400 648±5 698±7 19±2 139±10 12±2
The strength of Al-Mn-Zr alloys additions of Ce and Y showed a great variation with regard to composition
and thermal treatment. The Ce-containing alloy (Al-4Mn-1,2Zr-0,6Ce) showed the highest ultimate tensile
strength (UTS) of up to 990 MPa at room temperature (20 °C) after 350/400 °C treatment and outstanding
ductility (ψ = 42 45%), which is indicative of its high strain-hardening ability and refined microstructure. The
Y-modified alloy (Al-4Mn-1,2Zr-0,6Y) exhibited balance between strength and ductility, having UCS equal to
698 and 877 MPa and moderate plasticity. Conversely, the plain Al-4Mn-1,2Zr alloy exhibited the lowest
ductility, (psi < 3%, in most conditions and the highest UCS of 881 MPa at 450/400 C. All alloys showed
lower strengths, but higher elongation at the high temperature (350 0C), with the Ce-modified alloy retaining a
combination of high strength (up to 121 MPa YS) and high ductility (psi = 45%). This data points to the
strengthening effect of Ce addition in aluminum alloys as a major factor increasing ductility without reducing
UTS, therefore holding promise as an addition to high-performance, thermally stable aluminum alloys.
CONCLUSIONS
This study successfully demonstrates the synthesis, and characterization of high-alloyed Al-Mn-Zr-RE (Y, Ce)
alloys fabricated through mechanical alloying and hot press sintering. By systematically varying the rare earth
(RE) content and employing different sintering and annealing conditions, established a strong correlation
between microstructural evolution, phase transformations, and the resulting mechanical and thermal properties.
A detailed study that includes XRD examination, granule morphology, and microhardness and microstructure
analyses shed light on phase evolution, mechanical behavior and microstructural stability of the prepared
alloys.
XRD indicated that supersaturated with Mn and Zr solid solutions was formed due to dissolution of alloying
elements in the aluminum matrix after 10h of mechanical alloying while residual Al4Mn phase were observed
in the Al-Mn-Zr and Al-Mn-Zr-Y alloys, and Al6Mn formed in the Al-Mn-Zr-Ce alloy. SEM examination of
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the granule morphology showed that particles had been homogenously distributed with fine agglomeration.
Nanostructured grains of the (Al) and precipitates of intermetallic phases formed after mechanical alloying, hot
press sintering and annealing/aging processes at 350-450 °C and these factors contributed to the improved
properties.
SEM investigations revealed that Ce, Y, Zr, and Mn were homogeneously distributed in the alloy matrix after
milling and precipitation free zones formed during hot press sintering. Minor residual Fe contamination (~0.1–
0.2 %) from the milling media, as determined by the detection of Fe in the as-fabricated alloys, which agreed
to previous literature and not expected to have a substantial effect on alloy performance.
Microhardness results showed that samples sintered at 450 aged at 400°C were the hardest, indicating that
higher press sintering temperature and moderate annealing/aging temperature have effectively promoted a low
cavitation with precipitated strengthening without significant grain growth. Although the hardness decreased
slightly with extended annealing for 4 h in the alloys with rare earth elements, caused by grains and
precipitates coarsening.
The Al-Mn-Zr alloy demonstrated a high strength at ambient and elevated temperatures yield strength of 760
and 320 MPa and reduced ductility with 2,4 and 7% at room and 350 °C respectively. Additional alloying with
Y and Ce decreased yield strength while improved ductility for the similar treated alloys.
The stated results prove that the synergistic effects of alloying elements and high energy ball milling, with the
appropriate hot press sintering, make the alloys studied better at tolerating high temperatures and more
resistant to destruction.
RECOMMENDATIONS AND RESEARCH IMPLICATIONS
Optimize Rare Earths: Evaluate different contents and combinations of RE elements (e.g., Er, Gd, La) in order
to fine-tune phase distribution and mechanical properties.
Mechanical Property Profiling: Expand testing to tensile, fatigue, and creep behavior at elevated temperatures
for aerospace and energy sectors.
Oxidation and Corrosion Behavior: Investigate the surface stability of the alloys in oxidizing and corrosive
atmospheres to justify their potential use.
Demonstration of these superalloys in industrial practice Develop industrial application of these optimized
alloy systems.
In summary, this work provides a solid foundation for the design of advanced Al-based alloys with superior
structural and thermal properties, demonstrating the promising potential of mechanical alloying and hot press
sintering in next-generation material development.
REFERENCES
1. Flower H High Performance Materials In Aerospace, Springer Science and Media, 2012.
2. Gegel G Enabling technology for the design of short-fiber reinforced aluminum MMC components,
vol. 1, International Journal of Metalcasting, 2007, pp. 57-67.
3. Raiendrachari S "An overview of high-entrophy alloys prepared by mechanical alloying followed by
the characterization of their microstructuer and various properties," Alloys, 2022 vol. 1, no. 2, pp.
116-132,.
4. E A. Starke, J T Staley "Application of modern aluminum alloys to aircraft," Progress in Aerospace
Sciences , 1996 vol. 32, no. 2-3, pp. 131-172,.
5. J. Yang, Z. Zhu, S. Han, Y. Gu, Z. Zhu and H. Zhang, "Evolution Limitations Advantages and futuer
challenges of magnesium alloys as materials for aerospace applications," Journal of Alloys and
compounds , 2024 vol. 1008,.
INTERNATIONAL JOURNAL OF RESEARCH AND INNOVATION IN APPLIED SCIENCE (IJRIAS)
ISSN No. 2454-6194 | DOI: 10.51584/IJRIAS |Volume X Issue IX September 2025
www.rsisinternational.org Page 415
6. W.S Miller, L. Zhuang, J. Bottema, A. witterbood, P. Smet, A. Haszler and A. Vieregge, "Recent
development in Aluminium alloys for the automotive industry," Materials Science and Engineering ,
2000. vol. 280, no. 1, pp. 37-49,
7. Rajan j "DEVELOPMENT OF ULTRAFINE GRAINED A356 ALUMINIUM ALLOY BY
SEVERE PLASTIC DEFORMATION AND STUDIES ON ITS DEFORMATION BEHAVIOUR
AND MACHINABILITY," 2017. vol. 10.13140, no. RG.2.2.12032.74241,
8. R Lumley, "Introduction to aluminium metallurgy. InFundamentals of aluminium metallurgy,"
Woodhead Publishing, 2011. vol. 1, pp. 1-19,
9. Yakovtseva OA, Emelina NB, Mochugovskiy AG, Bazlov AI, Prosviryakov AS, Mikhaylovskaya
AV " Effect of Mechanical Alloying on the Dissolution of the Elemental Mn and Al-Mn Compound
in Aluminum," Metals, 2023. vol. 13, no. 1765,
10. Y. H. J. a. Martin J, "3D printing of high-strength aluminium alloys," Nature, 2017 vol. 549, pp. 365-
369,.
11. M. A. Z. M. G. I. Mochugovskiy AG, "Effect of heat treatment on the grain size control,
superplasticity, internal friction, and mechanical properties of zirconium-bearing aluminum-based
alloy," Journal of Alloys and Compounds, 2021. vol. 5,
12. L. D. Nam S.W, "The effect of Mn on the mechanical behavior of Al alloys," Metals and Materials,
2000. vol. 6, no. 1, pp. 13-16,
A. F. A. M. W. Buso S.J., "Characterization by TEM of a Supersaturated P/M Al-Mg-Zr Alloy after
Thermal Treatments," Material Science Forum, 2003 Vols. 426-432, pp. 4179-4184,.
13. H. J, "Aluminium in innovative light-weight car design," Materials transactions, 2011 vol. 5, pp. 818-
24,.
14. S. K. Prosviryakov AS, "Strngthening of mechanically alloyed Al-based alloy with high Zr contents,"
Materials Science and E ngineering , 2018 Jan 24. vol. 713, pp. 174-9,
15. Mikhaylovskaya AV, Kishchik AA, Tabachkova NY, Prosviryakov AS, Mochugovskiy AG
"Influece of seecondary Quasicryystalline I-phase preciptates on the grain structuer and mechanical
properties of the Al-Mg-Mn Alloy," Physics of metal and Metallography , 2022. vol. 123, no. 5, pp.
474-81,
16. Wang X, Liu J, Huang M, Zheng Y, Yang J, Li N, Dong X "A review on wear resistance of Mg
alloys: the influence of common rare earth alloying elements and general modification techniques,"
Materials Science and Technology, 2024. p. 02670836241262597,
17. Raabe D, Ponge D, Uggowitzer PJ, Roscher M, Paolantonio M, Liu C, Antrekowitsch H, Kozeschnik
E, Seidmann D, Gault B, De Geuser F, "Making sustainable alumiunum by recycling scrab.The
science of "dirty" alloys.," Progress in Materials science , 2022 Jul 1. vol. 128, p. 1000947,
18. Zheng Q."Recent Progress on Regulating Strategies for the Strengthening and Toughening of High-
Strength Aluminum Alloys," Materials, 2022. vol. 15(13), p. 4725,
19. Yakovtseva O.A. et al "Effect of high-energy ball milling on the microstructure, phase composition
and microhardness of the Al–Mn–Cu alloy," Izvestiya Vuzov Tsvetnaya.
20. Rana RS, Purohit R, Das S "Reviews on the influences of alloying elements on the microstructure
and mechanical properties of aluminum alloys and aluminum alloy composites," International
Journal Of Scientific and research publications, 2021 Jun 6.vol. 6, no. 2, pp. 1-,
21. Yakovtseva O.A. et al "Influence of Pre-Milling on the Mn Solid Solubility in the Al-Mn-Cu Alloy
during Mechanical Alloying," Metals(Basel), 2023 vol. 13, no. 4, p. 756,.
22. Cai Z, Liu H, Wang R, Peng C, Feng Y, Wang X "Microstructure and mechanical properties of the
extruded Al-Cu-Mn-Sc-Zr alloy during single-stage and two stage aging.," Journal of Materials
Enginerring and Performance , 2023 Jan vol. 32, no. 1, pp. 185-98,.
23. Suryanarayana C "Mechanical alloying and milling.," Progress in materials science, 2001 Jan 1 Vols.
(1-2), no. 46, pp. 1-84,.
24. Buso S.J., Almeida Filho A., Monteiro W.A. "High temperature Si–Ge alloy towards thermoelectric
applications," A comphernsive review Materials Today Physics, 2021. vol. 21,
25. Benjamin J.S "Dispersion strengthened superalloys by mechanical alloying.," Metallurgical
transaction, 1970 Oct 1. pp. 2943-51,
26. R. W. Cahn "Materials Science and Technology A Comprehensive Treatment," ed. Haasen P.K.J
Wiley- VCH, 1996 vol. 15, pp. 220-400,.
INTERNATIONAL JOURNAL OF RESEARCH AND INNOVATION IN APPLIED SCIENCE (IJRIAS)
ISSN No. 2454-6194 | DOI: 10.51584/IJRIAS |Volume X Issue IX September 2025
www.rsisinternational.org Page 416
27. Soni, P. R. "Application of surface active substance in mechanical alloying," Materials Science and
Engineering, 1991 vol. 134, pp. 1346-1349,.
28. Shingu P.H., Ishihara K.N "Metastable melting phenomena and solid state amorphization(SSA) by
mechanical alloying," J Alloys Compd, 1993 vol. 2, pp. 319-324,.
29. Alves, A. K., Bergmann, C. P., & Berutti, F. A. "High-Energy Milling In Novel Synthesis and
Characterization of Nanostructerd Materials," Engineering Materials Springer Berlin Heidelberg, vol.
10, pp. 978-3-642-41275-2-7, 2013.
30. Joy J, Krishnamoorthy A, Tanna A, Kamathe V, Nagar R, Srinivasan S, "Developments on the
Synthesis of Nanocomposite Materials Via Ball Milling Approch for Energy Storage Applications,"
Applied Sciences, vol. 12(18), p. 9312, 2022.
31. Murty BS, Ranganathan S, Rao MM "Solid State amorphization in binary Ti-Ni, Ti-Cu and ternary
Ti-Ni-Cu system by mechanical alloying," Materials Science and Engineering , vol. 149, no. 2, pp.
231-240, 1992.
32. Eckert J, Schultz L, Urban K Formation of quasicrystalline and amorphous phases in mechanically
alloyed Al-based and TiNi-based alloys, Acta Metallurica et Materialia, 1991. vol. 39, no. 7, pp.
1497-1506,
33. Pabi SK, Joardar J, Manna I, Murty BS. Nanocrystalline phases in Cu Ni, Cu Zn and Ni Al systems
by mechanical alloying. Nanostructured Materials. 1997 Jan 1;9(1-8):149-52..
34. Liu ZG, Guo JT, Ye LL, Li GS, Hu ZQ. Formation mechanism of TiC by mechanical alloying.
Applied physics letters. 1994 Nov 21;65(21):2666-8..
35. Klassen T, Herr U, Averback RS. Ball milling of systems with positive heat of mixing: Effect of
temperature in Ag-Cu. Acta materialia. 1997 Jul 1;45(7):2921-30
36. Benjamin JS, Volin TE. The mechanism of mechanical alloying. Metallurgical transactions. 1974
Aug;5(8):1929-34.,
37. Koch CC, Kim MS. The structure of amorphous alloys synthesized by mechanical alloying-non glass
forming systems. Le Journal de Physique Colloques. 1985 Dec 1;46(C8):C8-573..
38. Davis RM, McDermott B, Koch CC. Mechanical alloying of brittle materials. Metallurgical
Transactions A. 1988 Dec;19:2867-74.
39. Benjamin J.S "Mechanical alloying — A perspective," Metal Powder Report, vol. 45, no. 2, pp. 122-
127, 1990.
40. Lee PY, Koch CC. Formation of amorphous Ni‐Zr alloys by mechanical alloying of mixtures of the
intermetallic compounds Ni11,2Zr9 and NiZr2. Applied physics letters. 1987 Jun 1;50(22):1578-80.
41. Gilman PS, Benjamin JS. Mechanical alloying. Annual review of materials science. 1983
Aug;13(1):279-300.
42. Aikin BJ, Courtney TH. The kinetics of composite particle formation during mechanical alloying.
Metallurgical transactions A. 1993 Mar;24:647-57.
43. Aikin BJ, Courtney TH, "Modeling of Particle Size Evaluation During Mchanical Milling,"
Metallurgical TransactionsA., 1993 vol. 24, no. 11, pp. 2465-2471.
44. Aikin BJ, Courtney TH, Maurice DR. Reaction rates during mechanical alloying. Materials Science
and Engineering: A. 1991 Nov 15;147(2):229-37.
45. Yavari AR. Phase transformations in nanocrystalline alloys. Materials Science and Engineering: A.
1994 May 1;179:20-6.
46. Bordia RK, Camacho‐Montes H. Sintering: fundamentals and practice. Ceramics and Composites
Processing Methods. 2012 Apr 6:1-42
47. Kang SJ. Sintering: densification, grain growth and microstructure. Elsevier; 2004 Nov 27..
48. Chan KF, Zaid MH, Mamat MS, Liza S, Tanemura M, Yaakob Y. Recent developments in carbon
nanotubes-reinforced ceramic matrix composites: A review on dispersion and densification
techniques. Crystals. 2021 Apr 21;11(5):457.1 .
49. Yakovtseva OA, Mochugovskiy AG, Prosviryakov AS, Bazlov AI, Emelina NB, Mikhaylovskaya
AV. The microstructure and properties of Al–Mn–Cu–Zr alloy after high-energy ball milling and hot-
press sintering. Metals. 2024 Mar 6;14(3):310..
50. Fecht HJ, Hellstern E, Fu Z, Johnson WL. Nanocrystalline metals prepared by high-energy ball
milling. Metallurgical Transactions A. 1990 Sep;21:2333-7.
INTERNATIONAL JOURNAL OF RESEARCH AND INNOVATION IN APPLIED SCIENCE (IJRIAS)
ISSN No. 2454-6194 | DOI: 10.51584/IJRIAS |Volume X Issue IX September 2025
www.rsisinternational.org Page 417
51. Yavari AR. Metastable and nanocrystalline polymorphs of magnetic intermetallics. Materials Science
and Engineering: A. 1997 Jun 15;226:491-7.
52. Yavari AR "Mechanically Prepared Nanocrystalline Materials," Materials Transactions, JIM, , 1995
vol. 36, no. 2, p. 228–239.
53. Li S, Wang K, Sun L, Wang Z. A simple model for the refinement of nanocrystalline grain size
during ball milling. Scripta metallurgica et materialia. 1992 Aug 15;27(4):437-42..
54. Witkin DB, Lavernia EJ. Synthesis and mechanical behavior of nanostructured materials via
cryomilling. Progress in Materials Science. 2006 Jan 1;51(1):1-60..
55. Naik SN, Walley SM. The Hall–Petch and inverse Hall–Petch relations and the hardness of
nanocrystalline metals. Journal of Materials Science. 2020 Mar;55(7):2661-81..
56. Darling KA, Roberts AJ, Armstrong L, Kapoor D, Tschopp MA, Kecskes LJ, Mathaudhu SN.
Influence of Mn solute content on grain size reduction and improved strength in mechanically
alloyed Al–Mn alloys. Materials Science and Engineering: A. 2014 Jan 1;589:57-65.
57. Lei Z, Wen S, Huang H, Wei W, Nie Z. Grain refinement of aluminum and aluminum alloys by Sc
and Zr. Metals. 2023 Apr 12;13(4):751..
58. Ding W, Zhao X, Chen T, Zhang H, Liu X, Cheng Y, Lei D. Effect of rare earth Y and Al–Ti–B
master alloy on the microstructure and mechanical properties of 6063 aluminum alloy. Journal of
Alloys and Compounds. 2020 Jul 25;830:154685..
59. Wang X, Liu J, Huang M, Zheng Y, Yang J, Li N, Dong X. A review on wear resistance of Mg
alloys: the influence of common rare earth alloying elements and general modification techniques.
Materials Science and Technology. 2025 Jun;41(8):570-91..
60. Yang J, Zhu Z, Han S, Gu Y, Zhu Z, Zhang H. Evolution, limitations, advantages, and future
challenges of magnesium alloys as materials for aerospace applications. Journal of Alloys and
Compounds. 2024 Sep 25:176707..
61. Suryanarayana C "Evolution of mechanical alloying, Editor(s): Shashanka Rajendrachari,
Mechanical Alloying of Ferrous and Non-Ferrous Alloys," ,Elsevier, 2024. pp. 1-37,
62. Courtney TH, Maurice D. Process modeling of the mechanics of mechanical alloying. Scripta
Materialia. 1996 Jan 1;34(1):5-11
63. Davis RM, McDermott B, Koch CC. Mechanical alloying of brittle materials. Metallurgical
Transactions A. 1988 Dec;19:2867-74.
64. Weeber AW, Bakker H. Amorphization by ball milling. A review. Physica B: Condensed Matter.
1988 Oct 1;153(1-3):93-135.
65. M. B. Nie JF, "Comments on the “dislocation interaction with semicoherent precipitates (ω phase) in
deformed Al-Cu-Mg-Ag alloy," Scripta Materialia:, vol. 1:42, no. 4, pp. 409-13., 2000 Jan 3.
66. Ringer SP, Hono K. Microstructural evolution and age hardening in aluminium alloys: atom probe
field-ion microscopy and transmission electron microscopy studies. Materials characterization. 2000
Jan 1;44(1-2):101-31..
67. Sankaran KK, Mishra RS. Metallurgy and design of alloys with hierarchical microstructures.
Elsevier; 2017 Jun 14..