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J. Karloopia et al.
Introduction
Aluminium alloy-based particulate-reinforced metal matrix composites (MMCs) are
noted for their high specific strength [σ /ρ] and are extensively chosen for use in the
industries spanning automobile, aerospace, marine, ground transportation and few
other high-performance end products [1–3]. The metal matrix composites have also
engendered much interest for their selection and use in several commercial end products spanning both high performance-critical and low performance-critical. These
applications have almost always necessitated the need for high specific strength [σ /ρ]
and aluminum alloy-based metal-matrix composites are preferentially preferred due
to a combination of their improved properties to include low density, enhanced
wear resistance, good fatigue resistance, high strength, better thermal conductivity,
improved electrical conductivity, and low coefficient of thermal expansion [4]. In
spite of having few unique properties to offer, the metal matrix composites have often
found limited scope for purpose of applications primarily because of complications
arising from both processing and joining of the composites [5, 6].
The conventional welding or fusion-based welding of aluminum-based MMCs
is a challenging technique primarily because of gradual melting of the low melting
eutectics resulting from the elements present in its composition. This often results in
the initiation of one or more fine microscopic cracks during weld solidification [7,
8]. The solid state joining technique, such as friction stir welding (FSW), is ideally
suited for joining of the aluminum-based metal matrix composites. This process does
not cause melting, and thus the problems arising as a consequence of cracking during
weld solidification can be avoided [9–12]. This technique also helps in overcoming
other problems, which can often be associated with conventional welding, such as (i)
liquation cracking at the heat-affected zone, (ii) formation and presence of porosity,
(iii) reinforcement segregation, and (iv) the formation and presence of intermetallic
phases.
Friction stir welding is conducive for producing variations of the weld joint configuration, which can also include the butt joint. Friction stir welding of aluminum alloybased MMCs is a technologically-driven research topic that has engendered considerable scientific and technological interest due to its potential engineering applications
coupled with the numerous snags associated with the conventional welding processes.
Several researchers have found and recorded the advantages and shortcomings that
can be associated with friction stir welding of aluminum alloy-based MMCs.
(a) Liu and co-workers [11] examined optimum welding process parameters, and
its influence on both fracture behavior and tensile strength of an aluminum alloy
[2017-T351-based composite].
(b) Heurtier and co-workers [13] developed a 3-D thermomechanical model for
aluminum alloy 2024-T351 alloy using the technique of friction stir welding.
Their model provided a trajectory for the weld of each material, influence of
strain rate, microhardness in the various zones, and importantly an estimation of
temperature at the different locations. Both modeling and calibration techniques
J. Karloopia et al.
Introduction
Aluminium alloy-based particulate-reinforced metal matrix composites (MMCs) are
noted for their high specific strength [σ /ρ] and are extensively chosen for use in the
industries spanning automobile, aerospace, marine, ground transportation and few
other high-performance end products [1–3]. The metal matrix composites have also
engendered much interest for their selection and use in several commercial end products spanning both high performance-critical and low performance-critical. These
applications have almost always necessitated the need for high specific strength [σ /ρ]
and aluminum alloy-based metal-matrix composites are preferentially preferred due
to a combination of their improved properties to include low density, enhanced
wear resistance, good fatigue resistance, high strength, better thermal conductivity,
improved electrical conductivity, and low coefficient of thermal expansion [4]. In
spite of having few unique properties to offer, the metal matrix composites have often
found limited scope for purpose of applications primarily because of complications
arising from both processing and joining of the composites [5, 6].
The conventional welding or fusion-based welding of aluminum-based MMCs
is a challenging technique primarily because of gradual melting of the low melting
eutectics resulting from the elements present in its composition. This often results in
the initiation of one or more fine microscopic cracks during weld solidification [7,
8]. The solid state joining technique, such as friction stir welding (FSW), is ideally
suited for joining of the aluminum-based metal matrix composites. This process does
not cause melting, and thus the problems arising as a consequence of cracking during
weld solidification can be avoided [9–12]. This technique also helps in overcoming
other problems, which can often be associated with conventional welding, such as (i)
liquation cracking at the heat-affected zone, (ii) formation and presence of porosity,
(iii) reinforcement segregation, and (iv) the formation and presence of intermetallic
phases.
Friction stir welding is conducive for producing variations of the weld joint configuration, which can also include the butt joint. Friction stir welding of aluminum alloybased MMCs is a technologically-driven research topic that has engendered considerable scientific and technological interest due to its potential engineering applications
coupled with the numerous snags associated with the conventional welding processes.
Several researchers have found and recorded the advantages and shortcomings that
can be associated with friction stir welding of aluminum alloy-based MMCs.
(a) Liu and co-workers [11] examined optimum welding process parameters, and
its influence on both fracture behavior and tensile strength of an aluminum alloy
[2017-T351-based composite].
(b) Heurtier and co-workers [13] developed a 3-D thermomechanical model for
aluminum alloy 2024-T351 alloy using the technique of friction stir welding.
Their model provided a trajectory for the weld of each material, influence of
strain rate, microhardness in the various zones, and importantly an estimation of
temperature at the different locations. Both modeling and calibration techniques