78
A. Meher and M. M. Mahapatra
Several research studies have focussed on the tribological behavior of metal matrix
composites. Results reveal that the addition of ceramic particle reinforcement significantly enhances the wear resistance properties compared to the unreinforced material. Considering magnesium to be the matrix material makes the composite suitable
for use in lightweight structural applications spanning the industries of automobile
and aerospace. Researchers have also noticed some drawbacks specific to magnesium alloys, such as: (i) low stiffness (elastic modulus), (ii) inferior high-temperature
strength and creep resistance and (iii) low corrosion resistance and wear resistance
[2, 26]. These limitations can be overcome by the addition of suitable reinforcements
and a proper synthesis route. It was also found that a composite that was synthesized
by the in-situ process revealed better mechanical properties and tribological properties. In this study, an effort has been made to develop a magnesium alloy metal
matrix in situ composite [RZ5/10 wt.% TiB 2 ] by use of the self-propagating hightemperature synthesis route. The tribological behavior and wear surface morphology
of both the base alloy and the engineered composite were investigated.
Materials and Methods
Synthesis of RZ5/10 Weight Pct. TiB 2 Composites
Magnesium alloy metal matrix composite [RZ5/10 wt.% TiB 2 ] was prepared by an
in-situ synthesis technique of titanium diboride (TiB 2 ) reinforcements in the molten
magnesium alloy (RZ5) matrix. In the present investigation, magnesium alloy (Mg—
4.25% Zn—0.54% Zr—1.20% Ce), titanium mesh (of purity 99%) and boron powder
(of purity 99.5%) were used as the base materials. Stoichiometric amount of titanium
and boron were added to the magnesium alloy (RZ5) matrix to achieve 10 wt.% TiB 2 .
The self-propagating high temperature synthesis (SHS) process technique was used
for the synthesis of the composite [RZ5/10 wt.% TiB 2 ]. Details specific to synthesis of
the metal matrix composite are depicted in Fig. 1. Heat treatment of both the magnesium alloy and 10 wt.% TiB 2 reinforced magnesium alloy composite was carried out
as per procedures detailed in the Standard ASTM B661—12 to enhance both the
ductility and mechanical properties of the materials chosen and studied [27]. Similar
synthesis and heat treatment process was utilized for the development of 4 wt.%
TiB 2 , 6 wt.% TiB 2 and 8 wt.% TiB 2 composites in our earlier study. It was observed
that both heat treatment and addition of titanium diboride (TiB 2 ) reinforcement does
exert a significant influence on enhancing the mechanical properties [28].
A. Meher and M. M. Mahapatra
Several research studies have focussed on the tribological behavior of metal matrix
composites. Results reveal that the addition of ceramic particle reinforcement significantly enhances the wear resistance properties compared to the unreinforced material. Considering magnesium to be the matrix material makes the composite suitable
for use in lightweight structural applications spanning the industries of automobile
and aerospace. Researchers have also noticed some drawbacks specific to magnesium alloys, such as: (i) low stiffness (elastic modulus), (ii) inferior high-temperature
strength and creep resistance and (iii) low corrosion resistance and wear resistance
[2, 26]. These limitations can be overcome by the addition of suitable reinforcements
and a proper synthesis route. It was also found that a composite that was synthesized
by the in-situ process revealed better mechanical properties and tribological properties. In this study, an effort has been made to develop a magnesium alloy metal
matrix in situ composite [RZ5/10 wt.% TiB 2 ] by use of the self-propagating hightemperature synthesis route. The tribological behavior and wear surface morphology
of both the base alloy and the engineered composite were investigated.
Materials and Methods
Synthesis of RZ5/10 Weight Pct. TiB 2 Composites
Magnesium alloy metal matrix composite [RZ5/10 wt.% TiB 2 ] was prepared by an
in-situ synthesis technique of titanium diboride (TiB 2 ) reinforcements in the molten
magnesium alloy (RZ5) matrix. In the present investigation, magnesium alloy (Mg—
4.25% Zn—0.54% Zr—1.20% Ce), titanium mesh (of purity 99%) and boron powder
(of purity 99.5%) were used as the base materials. Stoichiometric amount of titanium
and boron were added to the magnesium alloy (RZ5) matrix to achieve 10 wt.% TiB 2 .
The self-propagating high temperature synthesis (SHS) process technique was used
for the synthesis of the composite [RZ5/10 wt.% TiB 2 ]. Details specific to synthesis of
the metal matrix composite are depicted in Fig. 1. Heat treatment of both the magnesium alloy and 10 wt.% TiB 2 reinforced magnesium alloy composite was carried out
as per procedures detailed in the Standard ASTM B661—12 to enhance both the
ductility and mechanical properties of the materials chosen and studied [27]. Similar
synthesis and heat treatment process was utilized for the development of 4 wt.%
TiB 2 , 6 wt.% TiB 2 and 8 wt.% TiB 2 composites in our earlier study. It was observed
that both heat treatment and addition of titanium diboride (TiB 2 ) reinforcement does
exert a significant influence on enhancing the mechanical properties [28].