Damage Mechanisms around Hardness Indentations in Ti ₃ SiC ₂

Abstract

Microstructural observations of damage around indentations in Ti 3 SiC 2 are presented. The Vickers hardness decreased with increasing load and asymptotically approached 4 GPa at the highest loads. No indentation cracks were observed even at loads as high as 300 N. Preliminary strength versus indentation plots indicate that, at least for the large‐grained material (is approximately100 μm) studied here, Ti 3 SiC 2 is a damage‐tolerant material able to contain the extent of microdamage to a small area around the indent. The following multiple energy‐absorbing mechanisms have been identified from scanning electron micrographs of areas in the vicinity of the indentation: diffuse microcracking, delamination, crack deflection, grain push‐out, grain pull‐out, and the buckling of individual grains.