28
S. Gupta
By analyzing the research on interpenetrating metal-MAX composites, we can
summarize that in these composites, the synergistic effects of metal and MAX phases
can be combined in the composite system. In a series of studies, Kothalkar and
co-workers [59, 60] designed interpenetrating composites of shape memory alloy
(Nitonol-NiTi) with MAX (Ti 2 AlC or Ti 3 SiC 2 ) phases. They also observed that
thermally cycled (TC) NiTi/Ti 3 SiC 2 showed the best response (Fig. 3) [60]. The
authors reported that at 200 MPa, the W d of (TC) NiTi/Ti 3 SiC 2 was 3 and 18 times
more than NiTi and fully dense Ti 3 SiC 2 , respectively. The authors proposed that this
phenomenon was due to the combinatorial damping effect of Ti 3 SiC 2 , NiTi, porosity,
interface between NiTi and Ti 3 SiC 2 , and thermal history of the composites.
Both NiTi [33] and Mg [35] are well-studied biomedical materials, thus the
enhancement of mechanical and damping behavior of these composites offers us
more option in designing biomedical devices. Fraczkiewicz and co-workers [99]
studied the effect of porosity on the mechanical and damping behavior of Ti 3 SiC 2 .
They reported 55% porous Ti 3 SiC 2 has density of 2.49 g/cc, Elastic Modulus (E)
of 26 GPa, 90% open porosity, UCS of 60 MPa, and W d of 0.016 MJ/m
3 at an
effective stress of ~93 MPa. Comparatively, cortical bone has a density of 1.8–
2.0 g/cc, modulus of 5–23 GPa, yield stress of 104.9–114.3 MPa, and Ultimate
Tensile Strength (UTS) of 35–283 MPa [35]. By comparing these results, it can be
hypothesized that MAX phases have also excellent potential as scaffold material
for biomedical applications. In this review, I am focusing on these composites from
techno-commercial perspective. Readers are requested to consult the cited references
for detailed methodology for calculating dissipated energy (W d ) from stress versus
strain plots.
MAX Phase Reinforced with Metallic or Ceramic Phases
with 0-3 Connectivity (Type-IV Composites)
In these composites, MAX phase forms the main matrix, and different particulates
can be added as particulate reinforcement in the structure (Fig. 1d). Hu and coworkers [81] observed in Ti 3 SiC 2 matrix composites reinforced with Al 2 O 3 (10 and
20 vol%) showed lower wear rates as the Al 2 O 3 concentration was increased in them.
The authors concluded that the presence of hard Al 2 O 3 particles reinforces the soft
Ti 3 SiC 2 matrix which lead to better tribological behavior. Nelson and co-workers
[84] also designed Ti 3 SiC 2 composites by reinforcing it with (1 and 6 vol%) Al 2 O 3
particulates. They did not observe any appreciable change in tribological behavior.
By comparing the two papers, we can conclude that further studies are needed to
optimize the Al 2 O 3 concentration in Ti 3 SiC 2 matrix.
Ho-Duc and co-workers [82] fabricated Ti 3 SiC 2 matrix reinforced with 30 vol%
SiC and TiC, respectively, by hot isostatic pressing at 1500 or 1600 °C for 8 h by
using a pressure of 200 MPa. The samples fabricated at 1600 °C, showed hardnesses
of 16 ± 2 and 15 ± 3 GPa for the Ti 3 SiC 2 composites reinforced with 30 vol% SiC
S. Gupta
By analyzing the research on interpenetrating metal-MAX composites, we can
summarize that in these composites, the synergistic effects of metal and MAX phases
can be combined in the composite system. In a series of studies, Kothalkar and
co-workers [59, 60] designed interpenetrating composites of shape memory alloy
(Nitonol-NiTi) with MAX (Ti 2 AlC or Ti 3 SiC 2 ) phases. They also observed that
thermally cycled (TC) NiTi/Ti 3 SiC 2 showed the best response (Fig. 3) [60]. The
authors reported that at 200 MPa, the W d of (TC) NiTi/Ti 3 SiC 2 was 3 and 18 times
more than NiTi and fully dense Ti 3 SiC 2 , respectively. The authors proposed that this
phenomenon was due to the combinatorial damping effect of Ti 3 SiC 2 , NiTi, porosity,
interface between NiTi and Ti 3 SiC 2 , and thermal history of the composites.
Both NiTi [33] and Mg [35] are well-studied biomedical materials, thus the
enhancement of mechanical and damping behavior of these composites offers us
more option in designing biomedical devices. Fraczkiewicz and co-workers [99]
studied the effect of porosity on the mechanical and damping behavior of Ti 3 SiC 2 .
They reported 55% porous Ti 3 SiC 2 has density of 2.49 g/cc, Elastic Modulus (E)
of 26 GPa, 90% open porosity, UCS of 60 MPa, and W d of 0.016 MJ/m
3 at an
effective stress of ~93 MPa. Comparatively, cortical bone has a density of 1.8–
2.0 g/cc, modulus of 5–23 GPa, yield stress of 104.9–114.3 MPa, and Ultimate
Tensile Strength (UTS) of 35–283 MPa [35]. By comparing these results, it can be
hypothesized that MAX phases have also excellent potential as scaffold material
for biomedical applications. In this review, I am focusing on these composites from
techno-commercial perspective. Readers are requested to consult the cited references
for detailed methodology for calculating dissipated energy (W d ) from stress versus
strain plots.
MAX Phase Reinforced with Metallic or Ceramic Phases
with 0-3 Connectivity (Type-IV Composites)
In these composites, MAX phase forms the main matrix, and different particulates
can be added as particulate reinforcement in the structure (Fig. 1d). Hu and coworkers [81] observed in Ti 3 SiC 2 matrix composites reinforced with Al 2 O 3 (10 and
20 vol%) showed lower wear rates as the Al 2 O 3 concentration was increased in them.
The authors concluded that the presence of hard Al 2 O 3 particles reinforces the soft
Ti 3 SiC 2 matrix which lead to better tribological behavior. Nelson and co-workers
[84] also designed Ti 3 SiC 2 composites by reinforcing it with (1 and 6 vol%) Al 2 O 3
particulates. They did not observe any appreciable change in tribological behavior.
By comparing the two papers, we can conclude that further studies are needed to
optimize the Al 2 O 3 concentration in Ti 3 SiC 2 matrix.
Ho-Duc and co-workers [82] fabricated Ti 3 SiC 2 matrix reinforced with 30 vol%
SiC and TiC, respectively, by hot isostatic pressing at 1500 or 1600 °C for 8 h by
using a pressure of 200 MPa. The samples fabricated at 1600 °C, showed hardnesses
of 16 ± 2 and 15 ± 3 GPa for the Ti 3 SiC 2 composites reinforced with 30 vol% SiC