Effect of microstructure on mechanical response of MAX phases

High density samples of Ti2AlC, a MAX Phase material, with three different grain sizes were processed by Reaction Sintering. The dynamic thermo-mechanical response of these samples was investigated by a modified Split Hopkinson Pressure Bar in conjunction with induction heating. Ti2AlC exhibits high compressive strength (above 600 MPa) for temperatures as high as 1100 °C under dynamic loading. The peak compressive stress decreases with increasing temperatures. Specimens exhibited catastrophic brittle failure at room temperature but graceful failure at high temperatures. Moreover, the temperature at which graceful failure occurs decreases with increasing grain size. Also, a Hall- Petch like relationship was observed between compressive strength and the grain diameter