Contact Damage Accumulation in Tic ₃ SiC ₂

Abstract

The evolution of deformation—;microfracture damage below Hertzian contacts in a coarse‐grain Ti 3 SiC 2 is studied. The Hertzian indentation stress—;strain response deviates strongly from linearity beyond a well‐defined maximum, with pronounced strain—;softening, indicating exceptional deformability in this otherwise (elastically) stiff ceramic. Surface and subsurface ceramographic observations reveal extensive quasi‐plastic microdamage zones at the contact sites. These damage zones are made up of multiple intragrain slip and intergrain shear failures, with attendant microfracture at high strains. No ring cracks or other macroscopic cracks are observed on or below the indented surfaces. The results suggest that Ti 3 SiC 2 may be ideally suited to contact applications where high strains and energy absorption prior to failure are required.