Vickers contact damage of micro-layered Ti 3SiC 2

Abstract

The nature, evolution, and degree of deformation microfracture damage around and beneath Vickers contacts in monophase Ti 3SiC 2 (312) are studied. The 312 material exhibits a pronounced shear deformation during indentation, indicating microscale plasticity which can be associated with infragrain multiple basal-plane slip between microlamellae, intergrain sliding, lamellae or grain pushout, 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 loading system and to distribute damage is somewhat akin to that of ceramics with either coarse-grained or heterogeneous microstructures, and perhaps geological structures.