Thermoelastic Micromechanical Stresses Associated with a Large α‐Silicon Carbide Grain in a Polycrystalline β‐Silicon Carbide Matrix

Abstract

The thermoelastic micromechanical stresses associated with a single large hexagonal α‐SiC grain within a fine‐grain‐size cubic (3C) β‐SiC matrix were calculated. The naturally occurring residual stresses which are created during cooling from the processing temperatures and the effects of superimposed applied external stresses are both considered. A significant effect of the shape or geometry of the α‐SiC grain is revealed, with the largest residual stresses associated with the naturally occurring tabular or platelet structure. The stresses are compared with the published strength results for these materials, which suggests that the residual stresses assume a significant role in the strength reduction that is observed.