High-temperature mechanical behavior of Ti 3 AlC 2 reinforced TiAl 3 based composites

Ti 3 AlC 2 /TiAl 3 composite has shown great potential for the lightweight high-temperature structural materials. Studying its high-temperature mechanical properties and revealing its high-temperature strengthening mechanisms is a highly challenging task. In this work, Ti 3 AlC 2 enhanced TiAl 3 matrix composites with different reinforcements mass fractions were successfully prepared at 1300°C by powder metallurgy route. Then, the high-temperature compressive properties of the composites were tested, and the macroscopic and microscopic structural morphologies of the compressed specimens were characterized. The results indicate that the high-temperature compressive properties of Ti 3 AlC 2 /TiAl 3 composites exhibit negative temperature sensitivity and positive strain rate sensitivity. At 900°C, the compressive peak stress of the 10-40Ti 3 AlC 2 /TiAl 3 composites is 16.6-41.3% higher than that of TiAl 3 matrix, indicating a significant strengthening effect. The pinning effect of Ti 3 AlC 2 particles on dislocations and grain boundaries, as well as the good interfacial bonding between Ti 3 AlC 2 particles and the TiAl 3 matrix, are the main reasons for improving the high-temperature compressive strength of Ti 3 AlC 2 /TiAl 3 composites.