Assessing the Mechanical Properties of an Aluminum- Copper-Magnesium Alloy

Abstract

This study aims to evaluate the mechanical behavior of Aluminum-Copper-Magnesium Alloy signifying the effect of adding magnesium to an alloy of Al-Cu to determine its potential for engineering applications. The research involved a series of processes, including melting the materials using a crucible furnace, followed by casting, machining, heat treatment, and subsequent testing. Five samples of the alloy were produced, with one serving as the control sample (96wt% Al + 4wt% Cu), and the remaining samples containing increasing percentages of magnesium ranging from 0.5wt% to 2wt%. Various mechanical tests, such as hardness, impact, flexural, and tensile tests, were conducted, along with microstructural analysis. The result revealed that adding magnesium to the base alloy (96wt% Al-4wt% Cu) increased the hardness of the aluminum alloy as the magnesium content increased. Additionally, the resistance to flexural force also demonstrated an upward trend with increasing magnesium content, up to 2wt%. However, analysis of the fracture surface indicated a decrease in ductility as the magnesium percentage increased. Furthermore, the material exhibited improved tensile strength, reaching its peak of 176.84N/mm 2 at 2wt% Mg while the lowest of 79.578N/mm² and 123.79N/mm² at 0wt% Mg (control) and 0.5wt%Mg respectively. Microstructural analysis unveiled that at 2wt% magnesium, the precipitation of magnesium occurred along the grain boundaries, forming flakes. Conversely, magnesium was uniformly distributed within the grains at lower magnesium percentages. These findings suggest that the addition of magnesium to Al-Cu alloy will greatly increase mechanical properties like hardness, tensile strength, and resistance to flexural force while decreasing ductility. The fractured surface in line with the microstructural analysis gives insight into mechanical failure and root cause through the composition and diffusion. Thus, magnesium proves positive for strength addition in Al-Cu alloy which is potentially can mitigate creeping-related issues. INTRODUCTION Materials selection plays a crucial role in engineering, surpassing the significance of the final product. Understanding the behavior of materials is imperative for their successful application. This study focuses on investigating the mechanical properties of an aluminum-copper-magnesium alloy for potential application in the automobile industry, castings, structural engineering, and high-strength, low-weight applications. While aluminum is widely available and possesses desirable characteristics such as ductility, malleability, corrosion resistance, and good thermal and electrical conductivity, it is often inadequate for certain structural and engineering applications. Therefore, it is essential to examine the behavior of aluminum alloys.

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Assessing the Mechanical Properties of an Aluminum-
Copper-Magnesium Alloy
1Ugwuoke, N. F., 2Onyia P. E., 3Onyia T. M., 4Nwogbu C. C., 5Iyida L. O., 6Agboeze N. A.
1,2,3,4&5 Department of Metallurgical and Materials Engineering,
Enugu State University of Science and Technology, Enugu, Nigeria.
*Corresponding Author Contacts; +2348103551255, ugwuoke.nnamdi@esut.edu.ng
ABSTRACT
This study aims to evaluate the mechanical behavior of Aluminum-Copper-Magnesium Alloy signifying
the effect of adding magnesium to an alloy of Al-Cu to determine its potential for engineering
applications. The research involved a series of processes, including melting the materials using a crucible
furnace, followed by casting, machining, heat treatment, and subsequent testing. Five samples of the alloy
were produced, with one serving as the control sample (96wt% Al + 4wt% Cu), and the remaining
samples containing increasing percentages of magnesium ranging from 0.5wt% to 2wt%. Various
mechanical tests, such as hardness, impact, flexural, and tensile tests, were conducted, along with
microstructural analysis. The result revealed that adding magnesium to the base alloy (96wt% Al-4wt%
Cu) increased the hardness of the aluminum alloy as the magnesium content increased. Additionally, the
resistance to flexural force also demonstrated an upward trend with increasing magnesium content, up to
2wt%. However, analysis of the fracture surface indicated a decrease in ductility as the magnesium
percentage increased. Furthermore, the material exhibited improved tensile strength, reaching its peak of
176.84N/mm2 at 2wt% Mg while the lowest of 79.578N/mm² and 123.79N/mm² at 0wt% Mg (control)
and 0.5wt%Mg respectively. Microstructural analysis unveiled that at 2wt% magnesium, the precipitation
of magnesium occurred along the grain boundaries, forming flakes. Conversely, magnesium was
uniformly distributed within the grains at lower magnesium percentages. These findings suggest that the
addition of magnesium to Al-Cu alloy will greatly increase mechanical properties like hardness, tensile
strength, and resistance to flexural force while decreasing ductility. The fractured surface in line with the
microstructural analysis gives insight into mechanical failure and root cause through the composition and
diffusion. Thus, magnesium proves positive for strength addition in Al-Cu alloy which is potentially can
mitigate creeping-related issues.
Keywords: Aluminum, Copper, Magnesium, Alloy, Hardness, Flexural, Bend, Impact, Mechanical
Properties, Microstructure, Microstructural Analysis, Alloy Composition, Aluminum Alloy, Al-Cu-Mg
INTRODUCTION
Materials selection plays a crucial role in engineering, surpassing the significance of the final product.
Understanding the behavior of materials is imperative for their successful application. This study focuses
on investigating the mechanical properties of an aluminum-copper-magnesium alloy for potential
application in the automobile industry, castings, structural engineering, and high-strength, low-weight
applications. While aluminum is widely available and possesses desirable characteristics such as ductility,
malleability, corrosion resistance, and good thermal and electrical conductivity, it is often inadequate for
certain structural and engineering applications. Therefore, it is essential to examine the behavior of
aluminum alloys.
International Journal of Innovative Scientific & Engineering
Technologies Research 11(3):36-49, July-Sept, 2023
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37
Alloys, which are metallic materials formed by combining two or more elements in a homogeneous
composition (French, 2018), offer distinct advantages over pure metals. While pure metals consist of
individual metal crystals that are malleable, soft, and possess high electrical conductivity, they are limited
in their applications. On the other hand, alloys exhibit improved corrosion resistance and are less
susceptible to changes in atmospheric conditions. Furthermore, the hardness of alloys can be modified
through specific heat treatments, and their conductivities can vary depending on the weight percentage of
the constituent elements.
Previous research by Kaufman (2008) mentioned that Aluminum-magnesium alloys offer the advantage
of being lighter compared to other aluminum alloys and are less prone to flammability issues associated
with high-magnesium alloys, however, this did not give in detail the compositions of these elements and
their mechanical orientations for diverse applications which this research is essential to bring to light. The
addition of copper to aluminum alloys contributes to significant strength improvements and enables
precipitation hardening (Raqaya et al, 2015), however, the inclusion of copper in aluminum can reduce
ductility and corrosion resistance. Definitely, the alloy of Al-Mg and Al-Cu will produce a new material
that needs the mechanical characteristics to be understood based on the percentage of the constituent
elements.
When selecting an appropriate alloy for a specific application, various factors come into play, including
tensile strength, density, ductility, formability, workability, weldability, and corrosion resistance
(Safranski and Gall, 2017). Therefore, it becomes essential to study the properties and effects of different
alloying elements and their quantities. Due to their high strength-to-weight ratio, aluminum alloys find
extensive use in aircraft (Stojanovic et al, 2018). Conversely, pure aluminum is too soft for such
applications and lacks the necessary tensile strength required for airplanes and helicopters. Hence,
alloying elements are added to aluminum to enhance its mechanical properties, and knowing the effect of
these elements and the amount of composition that will effect this desired change is necessary, thus the
significance of this study. Recent advancements in aluminum alloys have broadened the scope of
applications for wrought aluminum, replacing traditional aluminum castings.
The microstructures and mechanical properties of wrought aluminum alloys are highly influenced by
different working processes and thermal treatments according to Ny Khudair (2017), hence there is a vital
need to understudy the microstructural orientation of alloy and the effect of heat treatment and how it’s
going to affect the mechanical properties. The introduction of alloying elements has further enhanced the
mechanical properties of aluminum alloys, expanding their potential applications, particularly in the
aerospace and automotive industries (Ying et al, 2016). This progress signifies a significant step towards
utilizing wrought aluminum alloys in various engineering fields.
Through extensive research, engineers have made significant advancements in creating a wide range of
aluminum alloys aimed at enhancing their mechanical properties. Among the various alloying elements
utilized, copper and magnesium have emerged as particularly valuable. These elements possess distinct
properties that contribute to the improvement of aluminum's mechanical characteristics, thereby
increasing the likelihood of selecting aluminum alloys for diverse applications during the material
selection process. These metals possess distinct characteristics that contribute to their uniqueness and
importance in this research. Aluminum alloys offer economic advantages in numerous applications, as
mentioned by D Féron (2017), and have a diverse range of uses. However, some elements used in
aluminum alloys can be costly, and the preparation methods can be expensive due to the need for
precision during production.
In contrast, magnesium, another essential component in the study, is known to be inflammable in its
powdered form, and care must be taken during the casting stage to avoid oxides inclusions. These
inclusions can lead to changes in the properties of the final product, as highlighted by Vinojitha (2012).
Understanding and addressing these unique characteristics are crucial for the successful utilization of
these metals in various applications, hence, another significance of this study.
Molten magnesium tends to oxidize and burn unless care is taken to protect its surface against oxidation.
Unlike aluminum alloys which tend to form a continuous, impervious oxide skin on the molten bath
limiting further oxidation, magnesium alloys form a loose, permeable oxide coating on the molten metal
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38
surface. This allows oxygen to pass through and support burning below the oxide at the surface.
Protection of the molten alloy using either a flux or a protective gas cover to exclude oxygen is therefore
necessary. There are basically two main systems, flux, and flux less, for the melt protection of magnesium
alloys (Alil et al, 2015).
Considering the properties we are set to determine, hardness is the resistance of a material to localized
plastic deformation, ranging from super hard materials like diamonds to soft metals and plastics. Other
properties like toughness and strength also play a role, as hard materials may have low toughness and be
prone to fracture. Hardness can be assessed through indentation, scratch, and rebound hardness
measurements.
Strength is a material's ability to withstand applied loads without failure or plastic deformation. Al-Cu-
Mg alloy exhibits good mechanical strength and can be precipitation hardened to achieve strengths similar
to steel. Toughness, on the other hand, refers to a metal's ability to deform plastically and absorb energy
before fracture. A combination of strength and ductility contributes to toughness. It can be measured by
calculating the area under the stress-strain curve from a tensile test. When comparing the strength of Al-
Cu-Mg alloy with its weight, it is discovered that the ratio of strength to weight is always high (Joseph,
2011).
Ultimate tensile strength (UTS) represents a material's maximum resistance to fracture under simple
tension. It is an important measure for assessing a material's performance in applications. It’s therefore
very useful that this work will help influence decision-making on the choice of material in particular Al-
Cu-Mg alloy for a given application and the work performance of these materials can be predicted to give
the desired performance upon application. These will also help the producers during production to
understand the unique properties of each composition.
2.0 MATERIALS AND METHODS
2.1 Materials
 Aluminum billets of 98.9% purity.
 Copper powder of 98.5% purity.
 Manganese powder of 99.8 purity
 Crucible furnace.
 Permanent mold.
 Weighing balance.
 Universal tensile strength testing machine.
 Charpy Impact testing machine.
 Digital Rockwell hardness tester.
 Optical microscope
2.2 Methods
2.2.1 Samples Preparation
Materials used for this experiment include commercially available aluminum of 98.9 % purity in the form
of bundles of wires, 98.5 % pure copper, and 99.8% pure magnesium both in powdered metal form.
A permanent mold was specifically designed to manufacture standardized samples of an Al-Cu alloy.
The composition of the alloy consisted of 4 wt% copper and 96 wt% aluminum. Initially, the alloy was
produced as a billet with dimensions 40 mm in gauge diameter and 150 mm in gauge length, and upon
solidification, a precisely measured portion was selected for alloying with magnesium. The magnesium
content was incrementally increased from 0.5 wt% to 2 wt% while maintaining the aluminum-copper
alloy's overall percentage.
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Table 1 Chemical compositions of the Al-Cu-Mg alloy developed
S/N
Type of sample
Wt% of AlCu
Wt% of Mg
1
Al96Cu4
Control sample
100
0
2
AlCu99.5Mg0.5
Sample 1
99.5
0.5
3
AlCu99Mg1
Sample 2
99
1
4
AlCu98.5Mg1.5
Sample 3
98.5
1.5
5
AlCu98Mg2
Sample 4
98
2
To produce the desired samples, a total of 6000g of the alloy was required. An additional 600g was added
to account for casting risers, gating, and tolerance against waste. For measuring the alloy constituents, a
portable digital weighing machine was utilized, providing accurate measurements. The aluminum was
obtained in wire form, which was then cut into smaller pieces to facilitate efficient melting and ease of
measurement.
The crucible furnace used for melting the alloy was preheated to 200°C to eliminate any moisture content.
The melting temperature was carefully controlled and varied between 450°C to 1100°C, considering the
preheating, heat required for melting all constituents, and the homogenization process of the alloy
mixture.
To achieve proper homogenization, the constituents were charged into the crucible in a specific order
based on their melting point temperature and quantity. Al-Cu alloy was introduced first, followed by the
addition of Mg. It is important to note that precautions were taken during the addition of Mg to prevent
contact with atmospheric oxygen, as Mg readily reacts and is flammable. A pipe was used as a guide to
ensure the safe introduction of Mg into the alloy without exposure to oxygen.
In the experiment, a mold designed to accommodate 1200g of the alloy per charge was utilized, allowing
for the production of three samples in a single pour. The final test samples were cast in a steel pipe with
an internal diameter of 15mm and a gauge length of 200mm.
2.2.2 Method of Testing
Hardness tests were conducted using a Digital Rockwell hardness tester, 15mm sections were cut from
each sample, followed by grinding and polishing of the surface. Three indentations were made on each
sample, and the average value of the hardness was calculated from these three measurements. This
approach ensures a more accurate representation of the sample's hardness properties and minimizes the
potential impact of alloying element segregation.
A Charpy Impact testing machine was used to conduct the impact test, the samples were notched with a
3mm cut, with the notched side facing the direction of the impact force of 50 Joules.
For the flexural test, the triple point flexural test method was employed, with a span length of 55mm
using a Universal material tester. The flexural strength was read from the calibrated scale on the machine.
These tests assess the samples' ability to resist bending moments and provide essential data on their
toughness and resilience.
For the tensile test, the samples were machined to a gauge length of 70mm, a gauge diameter of 6mm, and
a gripping diameter was 13mm to fit into the Universal tensile testing machine. The ductility of the
material was calculated using the data from the tensile test as follows:
Percentage elongation (ductility) = ⨯
For the microstructural study, the sample underwent the following preparation steps:
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 Cutting: The sample was cut to the desired size for examination.
 Grinding: The cut sample was carefully ground to achieve a smooth and flat surface.
 Polishing: After grinding, the sample was polished to further refine the surface and remove any
surface imperfections.
 Etching: Kroll's solution, consisting of 25ml of HCl acid, 25ml of nitric acid, and 2ml of HF acid,
was used as the etchant. The sample was immersed in this solution for a specific duration of time
to reveal the microstructure.
 Rinsing: Once the etching process was complete, the sample was thoroughly rinsed to remove
any residual etchant.
 Drying: After rinsing, the sample was carefully dried to prevent any contamination.
Examination: The prepared sample was then examined using a Laboratory Electro-Optical Microscope.
This microscope allows for detailed observation and analysis of the sample's microstructure, providing
valuable information about its internal features, grain boundaries, and any defects present.
3.0 RESULTS
3.1 Hardness Variation of the Aluminum Alloy, Samples
Table 2 Readings of the hardness tests of the samples in HRC (Rockwell)
Samples
1st reading
2nd reading
3rd reading
Average
Control
0.5%
1%
1.5%
2%
45.6
38.7
57.7
70.6
74.6
32.6
52.6
51.9
68.8
72.8
50.4
49.2
66.5
70.2
72.4
42.87
46.83
58.7
69.9
73.26
Analysis of the readings taken from different parts of the polished face of the test samples reveals a clear
trend in hardness. The control sample, which contains 0% magnesium, exhibits the lowest average
hardness value. As the percentage of magnesium increases, the hardness of the samples also increases.
Notably, the sample with 2wt% magnesium demonstrates the highest hardness value, indicating that it is
the hardest among the tested samples. This observation suggests that the addition of magnesium
contributes to the enhancement of hardness in the alloy.
3.2 Fracture (Impact) Variation of the Aluminum Alloy Samples
Table 3 Readings of the impact test of the samples
Samples (%Mg)
Energy Absorbed (J)
Control
0.5%
1%
1.5%
2%
58
61
37.5
18
11
During the experiment, a total of 300 joules of energy was directed at the material, and the amount of
energy absorbed by the test samples was measured and recorded. The results, displayed on the right-hand
side of the table, indicate that the control sample absorbed 58 joules of energy. Surprisingly, the sample
with 0.5% magnesium absorbed the highest energy, measuring 61 joules, slightly higher than the control
sample. However, as the percentage of magnesium increases in the alloy, the energy absorbed by the
samples decreases. The sample with 2% magnesium exhibited the lowest absorbed energy despite having
the highest magnesium content. These findings indicate that the presence of magnesium in the aluminum-
copper alloy reduces its toughness, with the sample containing 2% magnesium demonstrating the lowest
toughness. However, it is interesting to note that the sample with 0.5% magnesium defies this trend by
exhibiting higher toughness than the control sample. This suggests that even a small amount of
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magnesium, as low as 0.5%, can strengthen the material. Another notable observation made during the
test was the behavior of the materials and their failure modes. Both the control sample and the 0.5%
magnesium sample exhibited high ductility, as they did not break but rather bent even with the presence
of a notch. In contrast, the samples with 1%, 1.5%, and 2% magnesium showed a brittle effect in their
failure modes, indicating reduced ductility.
3.3 Flexural Test Behavior of the Samples
Table 4 shows the Flexural test result of the control sample
FORCE (KN)
BEND (mm)
4
5
6
6.75
7.5
2
4
6
8
9
The Flexural strength (Fs) can be calculated using the formula below
Fs =
Where Fs = flexural strength of the material
P = load (force)
L = length of the span
b = thickness
d = width
From the experiment, our Length of span L is equal to 55mm, the width is equal to the thickness which is
equal to the diameter of the cylindrical test samples 15mm.
Therefore, = 183.3N/mm2
This is the maximum bending strength the control sample can withstand under flexural loading. Above
this, the material will start exhibiting a rapid increment in extension which will lead to failure.
Fig 1: Flexural chart of the control sample
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Table 5 Flexural test result of 0.5wt% Mg
Force (KN)
Bend (mm)
5
6.5
7.5
8
8.5
1
2
2.5
5
7
Fig 2: Flexural chart of 0.5wt% sample
The Flexural Strength Fs can be calculated using the formula below
Fs =
P=8.5kN
Substituting the values of the parameters, we have:
= 207.78N/mm2
The 0.5wt% can withstand a bending stress of 207.78N/mm2 above which the material will tend to fail.
Comparing the result of this with the control above, it can be seen that 0.5% can withstand more bending
force than the control.
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Table 6. The flexural result of the 1wt% Mg sample
Force (KN)
Bend (mm)
5
5.5
6.5
7
7.25
8
2
3
3.5
4
6
8
Fig 3: Flexural chart of 1wt% sample
Fs = = 195.55N/mm²
The maximum flexural strength is 195.55N/mm2 which is above the control sample but a little bit smaller
than the 0.5wt% sample.
Table 7. Flexural test result of the 1.5wt%Mg sample.
Force (KN)
Bend (mm)
5
7
8.5
8.75
2
4
7
11
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Fig 4: Flexural chart of 1.5wt% sample
Fs = = 213.9N/mm²
This sample shows a lot of flexural strength according to the value above. The flexural strength exceeded
the previous values gotten from the other samples.
Table 8 shows the flexural test result of the 2wt%Mg sample.
Force (KN)
Bend (mm)
5
6.75
7.75
8
9
2
4
6
7.5
10
Fig 5: Flexural chart of 2wt% sample
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Calculating the flexural strength using the formula we have:
Since the maximum force is 9kN
Therefore, Fs = = 220N/mm²
The maximum flexural strength of the material is 220N/mm². This is the material with the most flexural
strength. This material happens to be the one with the highest percentage of magnesium. Therefore, the
presence of magnesium in the alloy increases the resistance to bending force and also the rate of bending
before failure as the maximum extension is 10mm.
3.4 Tensile Test Of The Aluminum Alloy Samples
Table 9. Tensile test result of the control sample.
Force (KN)
Extension
1.25
1.5
2
2.25
1.5
0.15
0.30
0.90
1.05
1.15
From the table above, we can calculate the Stress σ, Strain ε, and the plot of Stress against Strain.
Stress, σ =F/A
Where: F is the force
A is unit Area.
Knowing the diameter to be 6mm, the area can be calculated using πd²/4 which is equal to 28.274mm²
Therefore,
Fig 6: Stress, Strain curve of the control sample
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Table 10. The tensile test result of the 0.5wt%Mg sample.
Force (KN)
Extension
1.5
2
2.5
3.5
3.25
0.5
0.35
0.75
1.15
1.35
(A) (B)
(C) (D)
Fig 7: A, B, C D; graph of 0.5wt%, 1wt%, 1.5wt% and 2wt% stress-strain curve
respectively
From the graph of the control sample above, the material exhibits an elastic range deformation up to a
Stress of 44.21N/mm² after which the plastic region begins. The material yield at the point of stress was
equal to 53.05N/mm², however, the Ultimate stress extended to 79.578N/mm² before the fracture
occurred at lower stress and higher strain of 53.06N/mm². For the 0.5wt% Mg, The UTS value is
123.79N/mm² which is the maximum tensile strength of the sample. After which the material failed at
114.94N/mm². This shows a very significant effect of magnesium on the alloy of aluminum and copper.
The yield stress of 1wt% Mg and that of 1.5wt% happen to be the same value but looking at the UTS
value, you discover that the 1.5wt% is higher thereby proving that 1wt% would withhold less force than
1.5wt%. The 1.5wt% has a yield point of 97.26N/mm² and the Ultimate stress of 150.3N/mm², this can be
described as the strain-hardened region.
One significant difference in the stress and strain curve for the 2wt% sample is that the material exhibited
a very low elastic region, however, proceeded with a plastic region that looks almost like the elastic
region. The plastic region is almost linear as that of the elastic. This significant change can be attributed
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to the behavior of the material due to the effect of the alloying element which created a strain-hardened
region. It’s as if the material is getting harder with the increase in stress. There’s enough resistance the
material has to offer to the increasing stress thereby giving it a longer time before failure will occur.
Immediately after the Ultimate stress of 176.84N/mm2, the material stress dropped and rupture occurred.
3.5 Comparison Of Ultimate Tensile Strength (UTS) Values
Looking at the tensile strength values, the highest value of stress in each of the samples represents the
Ultimate tensile strength of the sample. The control sample has the least with UTS of 79.578N/mm², the
UTS increases with increasing magnesium percentage to 176.84N/mm² for the 2wt% sample. It is
therefore noted that 2wt% Mg has the highest strength coupled with hardness but shows more brittleness
than the control sample and 1wt% sample.
3.6 Microstructural Analysis
The micrograph as was carried out using an optical microscope is shown below.
Fig 8: shows the microstructure of the control sample.
There are no phases of magnesium in the microstructure. The dark phase is an aluminum phase with
copper scatterings.
Fig 9: shows the micrograph of 0.5wt%Mg
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There are scattered magnesium-containing phases. Also, copper segregation can be seen in the phases
with aluminum. Some regions with dark shades cannot be categorically defined as it is beyond the scope
of this work.
Fig 10: shows the micrograph of 1wt%Mg
In this graph, there are more magnesium-containing phases than in 0.5wt%Mg. These increasing phases
can be seen in the hardness test as it increases the hardness property.
Fig 11: shows the micrograph of 1.5wt%Mg
Magnesium contains phases that can be seen forming flakes within the face of the sample.
Fig 12: shows the micrograph of the 2wt%Mg sample
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From the graph, we can see more magnesium flakes all over the face. The effect of magnesium contain
phases resulted in the hardness increase, and the fractured face during impact, and the tensile test also
shows the failure along the grain boundaries resulting in brittle-like failure.
4.1 CONCLUSION
In conclusion, this research confirmed that adding magnesium to aluminum-copper alloy increases
strength and precipitation hardening. Magnesium flakes along grain boundaries contribute to material
hardening but reduce ductility. These findings align with previous studies, validating magnesium's role in
improving aluminum-based alloys.
4.2 RECOMMENDATION
At low magnesium percentages (0.5wt% to 2wt %), aluminum copper alloy retains sufficient ductility and
strength. The balance between ductility and hardness in this range makes it suitable for advanced
applications in the automobile industry, airplane skeletons, and other engineering requiring high strength
and low weight. These alloys exhibit a high strength-to-weight ratio, making them ideal for structural
engineering. Despite some weakness in intergranular corrosion due to copper, the alloying and heat
treatment processes effectively distribute copper within the aluminum matrix, ensuring corrosion
resistance. Limitations such as impurity inclusions and power outages during testing suggest the use of an
electric furnace to avoid undesirable reactions. Additionally, these alloys offer superior heat dissipation,
machinability, and magnetic shielding properties.
In addition to the above, a further study focusing on the creep orientation of the alloy samples needs to be
studied.
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