Ternary Compound Ti<SUB>3</SUB>SiC<SUB>2</SUB>: Part II. Deformation and Fracture Behavior at Different Temperatures

Abstract

Compressive tests were conducted in vacuum at temperatures up to 1203 K, on the Ti 3 SiC 2 samples synthesized from 2Ti/2Si/3TiC powder mixture through pulse discharge sintering technique. The compressive strength of Ti 3 SiC 2 compound showed a monotonic decrease with increasing testing temperature. The Ti 3 SiC 2 samples displayed obvious brittle fracture behavior at temperatures below 1073 K. When the testing temperature was above 1123 K, obvious pseudo-plastic deformation behavior was observed in the stress-strain curves. At these temperatures, after an initial pseudo-strain-hardening, a decrease in stress follows with further increasing strain. The pseudo-plastic behavior of Ti 3 SiC 2 at temperature above 1123 K could be attributed to the basal plane slip, kink-band formation, delamination of layers at local sites, and intergranular cracking. Further increase in strain causes the growth and linkage of microcracks, which gives rise to the reduction of the real area of the cross section of specimen and hence lead to the strain-softening phenomenon.