The main objective of this present work is to determine the densification, hardness and impact strength behavior on LM09 alloy reinforced with graphite and magnesium oxide nano-particles. LM09 is lighter metal as compared to other engineering metals/alloys except magnesium and beryllium. In this research stir casting process was used to fabricate hybrid LM09 nano-composite. The composites were prepared by varying the proportion of reinforcements such as 1.2 wt.% graphite (constant) and 1.5-3.5 wt. % magnesium oxide. Densities of alloy and nano-composites were determined by using the rule of mixture and Archimedes principles. Composite with 1.2 wt. % graphite and 2.5 wt. % magnesium oxide have 95.75% of relative density. Theoretical and actual densities are closer so that the cast composites were produced with less porosity. The mechanical properties of nano-composite such as hardness and impact strength was measured and clearly show that the LM09 alloy is enhanced through the reinforcement of nano-particles. Hybrid nano-composite reinforced with 2.5 wt. % magnesium oxide dominates the hardness as compared to other composites (1.5 and 3.5 wt. % magnesium oxide) The increase in reinforcement particles enhances the impact strength proportionally. The present finding concludes that LM09 hybrid composite having 1.2 wt. % graphite and 2.5 wt. % magnesium oxide can be used for engineering applications.

1. Effect of Nano-Magnesium Oxide and Graphite Particles on Mechanical Properties of LM09 Hybrid Composites Fabricated by Stir Casting
IRJMSE
Effect of Nano-Magnesium Oxide and Graphite Particles
on Mechanical Properties of LM09 Hybrid Composites
Fabricated by Stir Casting
B. Selvam1*, M. Maria Jude2, M. Maheshwaran3, A. Manikandan4, S. Idayavarman5
1
School of Mechanical and Industrial Engineering, Ethiopian Institute of Technology-Mekelle, Mekelle University,
Ethiopia
2,3,4,5
Department of Mechanical Engineering, Mookambigai College of Engineering, Keeranur, Pudukkottai, India
The main objective of this present work is to determine the densification, hardness and impact
strength behavior on LM09 alloy reinforced with graphite and magnesium oxide nano-particles.
LM09 is lighter metal as compared to other engineering metals/alloys except magnesium and
beryllium. In this research stir casting process was used to fabricate hybrid LM09 nano-
composite. The composites were prepared by varying the proportion of reinforcements such as
1.2 wt.% graphite (constant) and 1.5-3.5 wt. % magnesium oxide. Densities of alloy and nano-
composites were determined by using the rule of mixture and Archimedes principles. Composite
with 1.2 wt. % graphite and 2.5 wt. % magnesium oxide have 95.75% of relative density. Theoretical
and actual densities are closer so that the cast composites were produced with less porosity. The
mechanical properties of nano-composite such as hardness and impact strength was measured
and clearly show that the LM09 alloy is enhanced through the reinforcement of nano-particles.
Hybrid nano-composite reinforced with 2.5 wt. % magnesium oxide dominates the hardness as
compared to other composites (1.5 and 3.5 wt. % magnesium oxide) The increase in reinforcement
particles enhances the impact strength proportionally. The present finding concludes that LM09
hybrid composite having 1.2 wt. % graphite and 2.5 wt. % magnesium oxide can be used for
engineering applications.
Keywords: aluminium alloy, metal matrix composite, graphite, nano-particle, densification, magnesium oxide.
INTRODUCTION
Metal matrix composites are used in many applications like
marine, automotive, structural and aerospace industries.
The researchers have been working to enhance the metal
matrix with suitable reinforcements for overcoming the
problems of the existing system. Aluminum and its alloys
are used for their ideal combination of properties such as
specific weight, good ductility, lightweight, better corrosion
resistance etc. (Lina et al., 2012). The steel can be
replaced by aluminium and its alloys to eliminate the major
drawback of steel such as corrosion and better conduction
of heat and electricity. Major reduction of weight is
achieved in the transport industries if aluminium and its
alloys used. Aluminium and its alloys are used in many
applications such as missiles, satellites, aerospace
components and architectural components. Even though,
the properties of aluminium alloys have to be enhanced for
making more suitable in the modern industrial applications.
Metal matrix composites are used in many applications as
compared to monolithic metal and alloys so that composite
materials use has been increased every day for industrial
applications. Metal matrix composites are produced
through various manufacturing techniques such as solid
state processing, liquid state processing, in-situ
processing, deposition techniques etc. (Surappa, 2003;
Hashim et al., 1992; Himashu et al., 2014; Karbalaei
Akbari et al., 2015).
*Corresponding author: B. Selvam, School of Mechanical and
Industrial Engineering, Ethiopian Institute of Technology-Mekelle,
Mekelle University, Ethiopia. E-mail: bselvam.eit@gmail.com. Tel:
+251-989846856. Fax : +251344409304 Co-Author Email :
2
mariajude2510@gmail.com Tel: +917708040112;
3
maheshmec94@gmail.com Tel: +919865508829;
4
appujeni2907@gmail.com Tel: +917904945475;
5
rockfortidhayan27@gmail.com Tel: +917010392741
International Research Journal of Materials Science and Engineering
Vol. 4(2), pp. 040-046, September, 2018. © www.premierpublishers.org. ISSN: 1539-7897
Research Article

2. Effect of Nano-Magnesium Oxide and Graphite Particles on Mechanical Properties of LM09 Hybrid Composites Fabricated by Stir Casting
Selvam et al. 041
There are many composite materials available but the
aluminum matrix composites particularly used for some
specific applications such as military, aircraft and
automotive industry structural components (Mohammad
Sharifi et al., 2011). Aluminium composites exhibit some
unique properties like superior physical properties, high
specific strength, resistance to environmental effects,
lightweight, high stiffness and wear resistance with
required mechanical properties (Lin et al., 2015; Meijuan
et al., 2016; Rawal, 2001; Casati and Vedani, 2014). Much
research work has been conducted to improve the
aluminium and its alloys specific properties through the
addition of nano-ceramic particles as reinforcements
(Alda. Et al., 2018).
Liquid state processing is the most economical composite
manufacturing method compared to other methods.
Specifically stir casting method has more advantages
among the liquid state processing (Diptikanta. Et al.,
2018). Simple and inexpensive processing, easy control
the matrix structures, suitable for mass production and
good bonding between particles are the major benefits of
stir casting technique. Casting method is required only
one-third of the cost as compared to other processing
methods (Skibo et al., 1988). This cost can be further
reduced to one-tenth for higher volume production.
Even though certain factors have to be closely monitored
and controlled during stir casting process such as
wettability, uniform distribution of reinforcement particles,
porosity and chemical reactions (Hashim et al., 1999).
Aluminium matrix composite can be made through stir
casting process. Quality of composites mostly depends on
the stir casting process parameters including stirring time,
stirrer speed, position of impeller, casting temperature and
pouring temperature.
Various types of ceramic reinforcement such as SiC,
Al2O3, MgO and B4C are used as reinforcement for the
aluminum alloy matrix (Alan and Andrew, 1991). The
reinforcements are added in the form of whisker or
particles or fibers to enhance strength, stiffness, wear
resistance, hot hardness in the aluminium metals/alloys
(Mavhungu et al., 2017; Sevik and Kurnaz, 2006;
Mazahery and Shabani, 2012).
LM09 Aluminium alloy which contains higher amount
silicon and it is employed to structural applications. LM09
alloy tensile strength is stable up to the temperature of
150oC and beyond this temperature its strength reduces
drastically, so that this alloy is not appropriate for elevated
temperature applications. In this paper, graphite and
magnesium oxide is used as reinforcement for improving
the properties of LM09 Matrix.
Generally aluminium matrix composites are reinforced with
micro or nano-sized particles mostly used for advanced
engineering applications for high performance
components. Usually additions of micro sized hard
particles are used to enhance the yield and ultimate
strength of the matrix metal. The metal matrix reinforced
with nano-sized ceramic particles will have higher strength
by maintaining superior ductility, fatigue strength and
higher creep behavior (Skolianos and Kattamis, 1993). But
the distribution of nano-particles uniformly and efficiently
in the matrix phase is the critical factor during the
manufacturing process of composites (Harichandran and
Selvakumar, 2016; Kang and Chan, 2004; Dominique et
al., 2010; Karbalae et al., 2013).
The graphite is well known due to its self-lubricating
property which used as a solid lubricant to reduce wear
and friction (Naplocha and Granat, 2008; Jun et al., 2004;
Liu et al., 1993). However, addition of graphite in the
aluminium matrix reveals adverse effects on hardness and
flexural strength (Jun et al., 2004).
Magnesium oxide (MgO) is a ceramic reinforcement which
mainly used to enhance wear resistance (Jun et al., 2004)
and mechanical properties. MgO nanoparticles are used in
order to provide greater surface area for homogenous
dispersion in the matrix for strengthening. Nanoparticles in
the matrix provide improved mechanical properties due to
reduced inter-particle spacing. However, nanoparticles
have a greater tendency toward agglomeration. So
required amount of MgO particle only has to be mixed with
matrix metal. Graphite and magnesium oxide together was
taken as reinforcement to obtain better physical and
mechanical properties. The main objective of this research
is to improve the existing properties of LM09 by reinforced
with graphite and magnesium oxide nano-particles. Due
to the addition of these reinforcements, the ultimate, yield
and compressive strength, creep behaviour, hardness and
wear properties are expected to enhance. LM09 is
extensively used as permanent mold for manufacturing
cover plates, instrument cases and low pressure castings.
LM09/graphite/magnesium oxide composite can be used
to increase the life of the mold by reducing wear rate and
the chances of higher temperature failures.
MATRIX AND REINFORCEMENT MATERIALS
DETAILS
The LM09 aluminium is an alloy mainly used for low
pressure die casting due to its good fluidity, other better
properties. The purchased LM09 was tested for its
compositions in the spark test lab. The result of the
compositions in weight % (wt. %) is shown in Table 1.
Table 2 shows that the standard chemical compositions of
LM09 alloy as per BS 1490: 1988 LM9.
Nano-particles of< 100nm magnesium oxides and graphite
particles of < 45nm were used as reinforcement for LM09
hybrid composites. The densities of graphite, magnesium
oxide and LM09 are 2.266, 3.58 and 2.68 g/cm3
respectively. The compositions and sample details are
provided in Table 3.

3. Effect of Nano-Magnesium Oxide and Graphite Particles on Mechanical Properties of LM09 Hybrid Composites Fabricated by Stir Casting
Int. Res. J. Mat. Sci. Engin. 042
Table 1: Chemical composition of matrix metal (LM09)
Elements Al Fe Mg Zn Cu Cr Ni Ca Pb Si
Composition % 88.06 0.338 0.406 0.035 0.08 0.04 0.0061 0.0062 0.0074 10.96
Table 2: Standard Chemical Composition of LM09
Elements Al Fe Mg Zn Cu Cr Ni Ca Pb Si
Composition % balance 0.6 max 0.2-0.6 0.1max 0.2max 0.05max 0.1max 0.05max 0.1max 10-13
Table 3: Composition of samples
Sample
Number
Amount
of Matrix
(wt. %)
Amount of
graphite
(wt. %)
Amount of
Magnesium
Oxide
(wt. %)
1 100 0 0
2 97.3 1.2 1.5
3 96.3 1.2 2.5
4 95.3 1.2 3.5
Figure 1a: Stir casting furnace set-up
Figure 1b: Pouring of molten composite in mold
EXPERIMENTAL PROCEDURE AND TESTING
The LM09/graphite-MgO nano-composite was fabricated
through stir casting technique. The required amount of
matrix and reinforcements was determined based on the
weight percentage. The required amount of LM09 solid
piece was pre-heated in the electric furnace at 550oC for 2
hours. The pre-heated matrix metal was placed in the
ceramic crucible and it was heated to above the melting
temperature at 750oC. The melt was degasified to remove
the hot gases for making defect free composite which was
done by adding solid hexa-chloro-ethane with matrix semi-
solid metal. The reinforcement powders such as graphite
and magnesium oxide nano powder were pre-heated
separately to remove moisture content at a temperature
around 600oC for 2 hours. After getting the molten LM09,
the pre-heated reinforcement particles were added in the
crucible. Motor attached stirrer was used to mix the
reinforcement particles uniformly in the matrix of LM09.
Stirrer was operated at 400 rpm for the period of 10
minutes. Further other than pure alloy samples, the
crucible with molten mixture contains metal matrix and
reinforcements was lifted from the furnace and stirred at a
speed of 300 rpm for 10 minutes to get uniform distribution
of reinforcements in the matrix phase. The molten
composite mixture was carefully poured in the mould
cavity and permitted to cool at room temperature. After
solidifying, composite specimens were removed from the
mould cavity. The specimens were produced in the stir
casting machine by considering various parameters
(Hashimi et al., 1999; Wang et al., 2008; Previtali et al.,
2008; Daoud and Abo-Elkhar, 2002). The cast composite
preforms were machined to get the required shape and
size for performing the various tests as per the ASTM
standards. The machined preforms were carefully stored
to avoid oxidation and other particles. Experimental set-up
used to fabricate the composite preforms is shown in
Figure 1.
Theoretical and actual densities were determined by using
the rule of mixtures and Archimede’s principle
respectively.The measured density values are tabulated in
Table 4. The theoretical density of composites was
determined by using the rule of mixture equation 1:
1
𝜌𝑐
=
1
(
𝐿𝑀09 𝑤𝑡. %
𝜌 𝐿𝑀09
+
𝑀𝑔𝑂 𝑤𝑡. %
𝜌 𝑀𝑔𝑂
+
𝑔𝑟𝑎𝑝ℎ𝑖𝑡𝑒 𝑤𝑡. %
𝜌 𝑔𝑟𝑎𝑝ℎ𝑖𝑡𝑒
)
(1)
Where ρc, ρLM09, ρMgO and ρgraphite are the densities of
composite, LM09, magnesium oxide and graphite
respectively
(a)
(b)

4. Effect of Nano-Magnesium Oxide and Graphite Particles on Mechanical Properties of LM09 Hybrid Composites Fabricated by Stir Casting
Selvam et al. 043
Actual densities were determined by both the methods of
analytical and Achimede’s principle for confirmation of
closure values. The actual density values calculated from
Archimede’s principle which is more accurate than
analytical method as shown in Table 4.
Table 4: Densities of alloy and composites
Sample
Number
Theoretical
Density
(gram/cm3)
Actual
density
(gram/cm3)
Relative
density
(%)
1 2.68 2.48 95.14
2 2.68 2.525 95.46
3 2.69 2.535 95.75
4 2.70 2.518 94.03
The specimen was machined to the required dimensions
of 10 x 10 x10 mm. Then the specimen preparation for
micro-hardness test was carried out. The SiC emery
sheets of grit having 400,600,800 and 1200 were used for
grinding the surfaces of the sample to remove the
unwanted materials. The samples were cleaned with water
and dried in between grinding of one grit sheet to another
grit sheet. The ground surface of samples was polished by
using the polishing machine. Diamond paste having
particle size of 1μm was used between the sample surface
and polishing wheel. Vicker’s micro-hardness machine
was used for measuring the hardness value as shown in
Figure 4. The hardness was measured through a diamond
indenter of having diamond diagonal 1360 by applying
loads 10, 25, 50, 100 & 200g. The dwell time of 15 seconds
was used for applying load. The loads of 10, 25, 50, 100 &
200g were selected to explore the variation of hardness
and get more accurate results. The dimensions of the
impression for the applied load were studied through the
image formed that was read by the system to determine
hardness. The hardness values were measured in 10
different places of the samples surface and average
values are used for constructing the Figure 5.
Figure 4: Micro-hardness test setup
RESULTS AND DISCUSSIONS
Influence of reinforcement addition on density
Densification behavior of alloy and LM09/graphite-MgO
hybrid nano-composites is shown in Figure 2 and 3. From
Figure 2, it is clearly shown that the actual density is very
closer to the theoretical density which proves that the cast
composites fabricated with less porosity. Theoretical
density of composites are almost same because densities
of matrix, magnesium oxide and graphite are 2.68,3.58
and 2.09 gram/cm3 respectively. Density increases from
the sample 1 to 3 with an increase in percentage of
reinforcement in the matrix phase. But the sample 4
observes that there is in reduced density value compared
to other samples. This low densification in sample 4 is due
to the agglomeration of reinforcement particles when
content of MgO is increased (Ansary et al., 2009). Hence
porosity of the sample 4 may be more compare to sample
2 and 3 as shown in Figure 2. The highest densification is
achieved in the sample 3 which consists of graphite 1.2 wt.
% and MgO 2.5 wt. %. Figure 3 shows that the relative
densities of hybrid nano-composites of LM09/graphite-
MgO. It is shown that the highest densification possible
when 2.5 wt. % of MgO oxide presents in LM09. But the
trend changes if the particles of reinforcement increase
beyond 2.5 wt. %.
Figure 2: Relation between theoretical and actual
densities of cast samples
0 1 2 3 4 5
90
92
94
96
98
Relativedensity(%)
Sample Number
Relative density
Figure 3: Relative densities of cast samples

5. Effect of Nano-Magnesium Oxide and Graphite Particles on Mechanical Properties of LM09 Hybrid Composites Fabricated by Stir Casting
Int. Res. J. Mat. Sci. Engin. 044
Influence of reinforcement addition on hardness
The variation of hardness for increased wt. % of
reinforcements is illustrated in Figure 5. Hardness value
decreases in the sample 2 as compared to pure LM09
sample due to the addition of graphite in the matrix phase.
The reduced hardness is observed in sample 2 due to the
property of graphite and it influences the dispersed
behaviour in the matrix as reported by Seah et al, 1995.
Further it reveals that sample 3 is having highest hardness
value than other samples. The reduction of hardness is
observed in the sample 4 due to the presence of higher
amount magnesium oxide particles (3.5 wt. %) as
compared to sample 3 (2.5 wt. %). Generally, the addition
of MgO up to a certain amount in the matrix phase leads
to increase in hardness, further it decreases the hardness
value (Balasubramanya et al., 2014). But the amount of
graphite particle addition increases influenced the
negative effect on hardness of the composite. From Figure
5 shows that the presence of hard MgO particles increases
the hardness by reducing the porosity in hybrid composite.
0 1 2 3 4 5
96
98
100
Micro-hardness(HV)
Sample number
Figure 5: Hardness values of cast samples
Impact Test (Charpy)
The test was done by using an impact testing machine and
the standard specimen for charpy method was machined
as per the ASTM E23.The specimen was machined to
dimensions of 55 x 10 x 10 mm having a v-notch of 2 mm
deep and 45o at a distance of 27.5mm from one side of the
sample. The swinging hammer was lifted to require height
and made to hit in opposite side of the specimen. The
energy absorbed during the impact of the specimen was
measured. The Charpy impact test measured values for
the various samples are shown in the Table 5.
Table 5: Charpy impact test of results
Sample Number Energy absorbed (joules)
1 1.8
2 2.4
3 3.0
4 3.5
The distribution of impact energy in the pure L09 and
composites is shown in the Figure 6. The addition of
reinforcements influences the toughness with respect to
the amount of particles of presents in the matrix phase.
Generally, addition of graphite particles may not be given
more influence as compared to the other ceramic particles.
But addition of MgO with LM09 has made great influence
on the impact energy. The energy absorbed by the
samples greatly increases with the amount of increase in
reinforcement particles of MgO as shown in Figure 6.
LM09 toughness capacity increases while the MgO was
reinforced. The highest toughness values are achieved at
the higher amount of MgO addition to the matrix alloy.
From Figure 6, almost double time of impact energy is
enhanced in the composite having 3.5% MgO
reinforcement particles.
0 1 2 3 4 5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
Energyabsorbed(joules)
Sample Number
Figure 6: Charpy impact test values of casted samples
CONCLUSIONS
Graphite-magnesium oxide reinforced LM09 matrix hybrid
nano-composite has been fabricated and investigated
densification behavior, hardness, and impact energy.
Through the experimental investigations of tests the
following conclusions are obtained.
1. It is observed that increase in density of composites
having 1.5 and 2.5 wt.% of MgO as compared to
LM09. But the composite having 3.5 wt. % MgO has a
decreases in density due to the agglomeration of
reinforcement particles in the LM09 matrix. The actual
densities are closer to the theoretical densities so that
the cast nano-composites have less porosity. Highest
densification is achieved while 2.5 wt. % magnesium
oxide particles present in the composite.
2. There is a decrease in hardness observed in a nano-
composite reinforced by 1.2 wt. % of graphite and 1.5
wt % of MgO due to the addition of graphite. However,
the increase in density is observed in the composite
reinforcement while adding from 1.5 to 2.5 wt. % of
MgO and the decrease in hardness takes place
beyond the 2.5 wt. %. This change in behavior of
hardness value due to the addition of graphite and

6. Effect of Nano-Magnesium Oxide and Graphite Particles on Mechanical Properties of LM09 Hybrid Composites Fabricated by Stir Casting
Selvam et al. 045
MgO in the LM09 matrix phase. Since graphite is a soft
and dispersed in the matrix so it reduces hardness of
the matrix. Also, the addition of MgO improves
hardness up to a certain level to increase in hardness,
further it decreases the hardness value.
3. Impact test results prove that impact energy
absorption capacity is increased with increase in % of
reinforcement with respect to the all composites.
The remarkable properties of toughness and hardness
have been enhanced the LM09 matrix with reinforcements
(graphite and MgO). This composite can be used for the
application of high pressure die casting with enhanced life
cycles as compared unreinforced die.
REFERENCES
Alan L. Geiger, Andrew Walker J. (1991). The processing
and properties of discontinuously reinforced aluminium
composites. J. Mater. 43(8): 8-15.
Alda Afkham, Rasoul Azari Khosroshahi, Sajed
Rahimpour, Cassra Aavani, Reza Taherzadeh
Mousavian (2018). Enhanced mechanical properties of
in situ aluminium matrix composites reinforced by
alumina nanoparticles. Arch. Cv. Mech. Eng. 18(1):
215-226.
Ansary YA, Montazerian,M, Abdizadeh H.
(2009). Microstructure and mechanical
properties of aluminum alloy matrix composite
reinforced with nano-particle MgO. J. Alloys Compd.
884(1-2): 400–404.
Balasubramanya HS, Sharana Basavaraja, Srinivas S,
Ravikumar V. (2014). Wear behave of as cast and heat
treated hybrid Aluminium Metal Matrix Composites.
Procedia Mater. Sci. 5(1): 1049 – 1055.
Casati, R, Vedani M. (2014). Metal Matrix Composites
Reinforced by Nano-Particles—A Review.
Metals, 4 (1): 65-83.
Daoud A, Abo-Elkhar M. (2002). Influence of Al2O3 or ZrO2
particulate addition on the microstructure aspects of
AlNi and AlSi alloys. J. Mater. Proces. Technol. 120(1-
3): 296–302.
Diptikanta Dasa, Purna Chandra Mishra, Anil Kumar
Chaubey, Chandrika Samal (2018). Characterization of
the developed aluminium matrix composites-an
experimental analysis. Mater Today, 5(1): 3243–3249.
Dominique P, Drew RAL, Trudeau ML. (2010). Fabrication
and properties of mechanically milled
alumina/aluminum nanocomposites. Mater. Sci. Eng.
A, 527(29-30): 7605-7614.
Harichandran R, Selvakumar N. (2016). Effect of
nano/micro B4C particles on the mechanical properties
of aluminium metal matrix composites fabricated by
ultrasonic cavitation-assisted solidification process.
Arch. Cv. Mech. Eng. 16(1): 147-158.
Hashim J, Looney L, Hashmi,MSJ. (1999). Metal matrix
composites: production by the stir casting method. J.
Mater. Proces. Technol. 92-93(1): 1-7.
Himashu Kala, Mer KKS, Sandeep Kumar (2014). Review
on mechanical and tribological behaviors of stir cast
aluminium matrix composites. Procedia Mater. Sci.
6(1): 1951-1960.
Jun D, Yao-hui L, Si-rong Y, Wen-fang L. (2004). Dry
sliding friction and wear properties of Al2O3 and carbon
short fibres reinforced Al–12Si alloy hybrid composites.
Wear, 257(9-10): 930–940.
Kang YC, Chan SLI (2004). Tensile properties of
nanometric Al2O3 particulate reinforced aluminum
matrix composites. Mater. Chem. Phys. 85(2-3): 438–
443.
Karbalaei Akbari M, Mirzaee O, Baharvandi H.
(2013). Fabrication and study on mechanical properties
and fracture behavior of nanometric Al2O3 particle-
reinforced A356 composites focusing on the
parameters of vortex method. Mater. Des. 46(1): 199–
205.
Karbalaei Akbari M, Baharvandi, HR, Shirvanimoghaddam
K. (2015). Tensile and fracture behavior of nano/micro
TiB2 particle reinforced casting A356 aluminum alloy
composites. Mater. Des. 66(A): 150–161.
Lin Jiang, Hanry Yang TaoHu, Troy Topping, Dalong
Zhang, Enrique J. Lavernia, Julie M Schoenung (2015).
Influence of length-scales on spatial distribution and
interfacial characteristics of B4C in a nanostructured Al
matrix. Acta Mater. 89(1): 327-343.
Lina YC, Qi-Fei Li, Yu-Chi Xia, Lei-Ting Li (2012). A
phenomenological constitutive model for high
temperature flow stress prediction of Al–Cu–Mg alloy.
Mater. Sci. Eng. A, 534(1): 654– 662. Liu Y, Rohatgi
PK, Ray S. (1993). Tribological characteristics of
aluminum-50 Vol Pct graphite composite.Metall. Trans.
A. 24(1): 151–159. Mavhungu ST, Akinlabi ET, Onitiri
MA, Varachia FM (2017). Aluminium Matrix composites
for Industrial use: Advances and Trends. Procedia
Manuf. 7(1): 178-182.
Mazahery A, Shabani MO (2012). Nano-sized silicon
carbide reinforced commercial casting aluminum alloy
matrix: Experimental and novel modeling evaluation.
Powder Technol. 217(1): 558–565.
Meijuan Li, Kaka Ma, Lin Jiang, Hanry Yang, Julie M
Schoenung (2016). Synthesis and mechanical
behavior of nanostructured Al 5083/n-TiB2 metal matrix
composites. Mater. Sci. Eng. A, 656 (1): 241-248.
Mohammad Sharifi E, Karimzadeh F, Enayati M H (2011).
Fabrication and evaluation of mechanical and
tribological properties of boron carbide reinforced
aluminum matrix nano-composites. Mater. Des. 32 (6):
3263-3271.
Naplocha K, Granat K. (2008). Dry sliding wear of
Al/Saffil/C hybrid metal matrix composites. Wear,
265(11-12): 1734–1740.
Previtali B, Pocci D, Taccardo C. (2008). Application of
traditional investment casting process to aluminium
matrix composites. Composite Part A: Appll. Sci.
Manuf. 39(10): 1606–1617.
Rawal S. (2001). Metal-Matrix Composites for Space
Applications. JOM, 53(4): 14-17.

7. Effect of Nano-Magnesium Oxide and Graphite Particles on Mechanical Properties of LM09 Hybrid Composites Fabricated by Stir Casting
Int. Res. J. Mat. Sci. Engin. 046
Seah KHW, Sharma SC, Girish BM (1995). Effect of
artificial ageing on the hardness of cast ZA- 27/graphite
particulate composites. Mater. Des. 16(6): 337-341
Skolianos S, Kattamis TZ (1993). Tribological properties of
SiC-reinforced Al–4.5% Cu–1.5% Mg alloy composites.
Mater. Sci. Eng. A, 163(1): 107–113.
Sevik H, Kurnaz S. (2006). Properties of alumina
particulate reinforced aluminum alloy produced by
pressure die casting. Mater. Des. 2006, 27(8): 676–
683.
Skibo DM, Schuster L Jolla (1988), US Patent No. 4 786
467. 198
Surappa MK (2003). Aluminium matrix composites:
Challenges and opportunities. Sadhana, 28(1-2): 319-
334.
Wang XJ, Hu XS, Wu K, Deng KK, Gan WM, Wang CY,
Zheng MY (2008). Hot deformation behavior of
SiCp/AZ91 magnesium matrix composite fabricated by
stir casting. Mater. Sci. Eng. A, 492(1-2): 481–485.
Accepted 5 July 2018
Citation: Selvam B, Maria Jude M, Maheshwaran M,
Manikandan A, Idayavarman S (2018). Effect of Nano-
Magnesium Oxide and Graphite Particles on Mechanical
Properties of LM09 Hybrid Composites Fabricated by Stir
Casting. International Research Journal of Materials
Science and Engineering, 4(2): 040-046.
Copyright: © 2018 Selvam et al. This is an open-access
article distributed under the terms of the Creative
Commons Attribution License, which permits unrestricted
use, distribution, and reproduction in any medium,
provided the original author and source are cited.