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A. Meher and M. M. Mahapatra
lighter than aluminum and 75% lighter than steel. Magnesium alloys also have high
strength-to-weight ratio, good machinability and dimensional stability. Because of
this, nowadays, researchers are putting effort to replace aluminium and steel with
different magnesium alloys [2]. Along with that, reinforcing magnesium alloys with
ceramic particulates helps to enhance its mechanical properties [3]. The properties
of the developed composites mostly depend on the synthesis route and the types and
volume fraction of the reinforcement used.
In conventional composite synthesis process, the ceramic reinforcement is directly
added to the magnesium alloy matrix and this is known as ex-situ composites.
The resultant composite that is developed using this process shows poor wettability coupled with the formation and presence of some interfacial products. To
overcome these drawbacks, various research effort has been made to synthesize
the reinforcement during the synthesis of the composite and this is called as an in
situ composite. Utilizing this process, strong interfacial bonding, thermodynamically stable reinforcements and uniform distribution of the fine reinforcing particles
were observed [4]. Generally, titanium carbide (TiC), titanium diboride (TiB 2 ) and
aluminum diboride (AlB 2 ) reinforced metal matrix composites are synthesized using
this process [5, 6]. Among the various reinforcements available for the synthesis of
particulate-reinforced metal matrix composites, TiB 2 is considered as the best candidate primarily because of its high melting point, hardness and elastic modulus [7].
Several independent research studies have been done with the primary objective of
studying the effect of reinforcements on an improvement of the mechanical properties
of monolithic materials [8].
Wear generally occurs on the surface of the material due to atmospheric exposure
or by continuous sliding of one surface over another or even in moving components.
So, wear of the materials is the most common problem for the industries nowadays
[9]. Among different types of wear, abrasive wear is the fastest form of wear occurring
on a material and is a big challenge for industries. It occurs due to the presence of hard
abrasive particles that come in-between the contact surfaces. Due to a continuous
sliding of the materials with the abrasive surface, the material at the surface gradually
wears out and is often displaced in the form of chips [10]. The wear of materials
can be reduced by enhancing both the surface hardness and strength of the chosen
material.
Magnesium alloy is preferred for use in various components, such as: (i) transmission casing of aerospace, (ii) alloy wheel, (iii) seat frame, (iv) roof frame and (v)
engine casing of automobiles. Achieving an improvement in the tribological properties of the material is both desirable and essential [11]. The tribological properties of
the chosen magnesium alloy can be improved either by the addition of a new element
to the conventional alloy or by the use of strain hardening [12, 13]. Also, the addition of hard ceramic particles to the soft magnesium alloy matrix does contribute
to enhancing the surface hardness, which acts as a resistance to plastic deformation. Researchers have developed magnesium alloy-based metal matrix composites
by reinforcing with various ceramic particles, such as aluminum oxide (Al 2 O 3 ),
silicon carbide (SiC), titanium diboride (TiB 2 ) and boron carbide (B 4 C) or by the
use of carbonaceous materials, such as: carbon nanotube (CNT) and graphite powder,
A. Meher and M. M. Mahapatra
lighter than aluminum and 75% lighter than steel. Magnesium alloys also have high
strength-to-weight ratio, good machinability and dimensional stability. Because of
this, nowadays, researchers are putting effort to replace aluminium and steel with
different magnesium alloys [2]. Along with that, reinforcing magnesium alloys with
ceramic particulates helps to enhance its mechanical properties [3]. The properties
of the developed composites mostly depend on the synthesis route and the types and
volume fraction of the reinforcement used.
In conventional composite synthesis process, the ceramic reinforcement is directly
added to the magnesium alloy matrix and this is known as ex-situ composites.
The resultant composite that is developed using this process shows poor wettability coupled with the formation and presence of some interfacial products. To
overcome these drawbacks, various research effort has been made to synthesize
the reinforcement during the synthesis of the composite and this is called as an in
situ composite. Utilizing this process, strong interfacial bonding, thermodynamically stable reinforcements and uniform distribution of the fine reinforcing particles
were observed [4]. Generally, titanium carbide (TiC), titanium diboride (TiB 2 ) and
aluminum diboride (AlB 2 ) reinforced metal matrix composites are synthesized using
this process [5, 6]. Among the various reinforcements available for the synthesis of
particulate-reinforced metal matrix composites, TiB 2 is considered as the best candidate primarily because of its high melting point, hardness and elastic modulus [7].
Several independent research studies have been done with the primary objective of
studying the effect of reinforcements on an improvement of the mechanical properties
of monolithic materials [8].
Wear generally occurs on the surface of the material due to atmospheric exposure
or by continuous sliding of one surface over another or even in moving components.
So, wear of the materials is the most common problem for the industries nowadays
[9]. Among different types of wear, abrasive wear is the fastest form of wear occurring
on a material and is a big challenge for industries. It occurs due to the presence of hard
abrasive particles that come in-between the contact surfaces. Due to a continuous
sliding of the materials with the abrasive surface, the material at the surface gradually
wears out and is often displaced in the form of chips [10]. The wear of materials
can be reduced by enhancing both the surface hardness and strength of the chosen
material.
Magnesium alloy is preferred for use in various components, such as: (i) transmission casing of aerospace, (ii) alloy wheel, (iii) seat frame, (iv) roof frame and (v)
engine casing of automobiles. Achieving an improvement in the tribological properties of the material is both desirable and essential [11]. The tribological properties of
the chosen magnesium alloy can be improved either by the addition of a new element
to the conventional alloy or by the use of strain hardening [12, 13]. Also, the addition of hard ceramic particles to the soft magnesium alloy matrix does contribute
to enhancing the surface hardness, which acts as a resistance to plastic deformation. Researchers have developed magnesium alloy-based metal matrix composites
by reinforcing with various ceramic particles, such as aluminum oxide (Al 2 O 3 ),
silicon carbide (SiC), titanium diboride (TiB 2 ) and boron carbide (B 4 C) or by the
use of carbonaceous materials, such as: carbon nanotube (CNT) and graphite powder,