Anisotropic strength and plastic deformation behavior of MAX phase Ti₃AlC₂ under ultrahigh pressure

Machinable layered ternary carbides and nitrides (MAX) are a class of multifunctional materials combining advantages of both ceramics and metals, and are of vital technological importance. The study on the mechanical behavior is very critical for their realistic application and failure diagnose. However, there is still no in situ investigation on their strength and plastic deformation under high pressure/stress. Here, we study the strength and texture development of Ti3AlC2 under nonhydrostatic pressure up to 41 GPa. The strength anisotropy was clearly seen and lattice stress states of different planes were obtained. The highest differential stresses supported by (10-10) plane and (0008) plane at 41 GPa are about 13.7 GPa and 4.5 GPa, respectively. The average strength is higher than that of stishovite, one of the strongest oxides. Strong 0001 deformation texture developed under ultra-high stress. This work clearly reveals the lattice-stress states and deformation behavior of Ti3AlC2 under high stress, which provides direct experimental guidance on the material design and processing for MAX phases.