Vickers contact damage of micro-layered Ti3SiC2

The nature, evolution, and degree of deformation-microfracture damage around and beneath Vickers contacts in monophase Ti3SiC2 (312) are studied. The 312 material exhibits a pronounced shear deformation during indentation, indicating microscale plasticity which can be associated with intragrain multiple basal-plane slip between micro-lamellae, intergrain sliding, lamellae or grain push-out, and microfailures at the ends of the constrained shear-slips. No contact-induced cracks are observed and the micro-damage is widely distributed within the shear-compression zone around and below the contacts. The damage process is stochastic which results from a complex interplay of statistical variation in both relative size and crystallographic orientation of individual grains. The ability of 312 to absorb energy from the loaning system and to distribute damage is somewhat akin to that of ceramics with either coarse-grained or heterogeneous microstructures, and perhaps geological structures. (C) 1998 Elsevier Science Limited. All rights reserved.