A Soft Ceramic Ti_3SiC_2 with Microscale Plasticity at Room Temperature

摘要

Microscale plasticity of Ti_3SiC_2 was investigated by Vickers hardness indentation. The surface layer of the hardness indentations was removed by acid solution to observe microstructure beneath the indentations, where a large number of bending, delamination and kinking grains were found. These features suggest that Ti_3SiC_2 is able to consume microdamage around the indentations. Numerous basal plane dislocations and stacking faults lying in Ti_3SiC_2 grains or accumulating at grain boundaries were observed. The basal plane dislocations play an important role in the microscale plastic deformation. The plasticity and damage tolerance for Ti_3SiC_2 at room temperature should be attributed to multiple energy absorbing mechanisms: grains bending, delamination, kink-band formation, and the basal plane slip, etc.