Onset Plastic Deformation and Cracking Behavior of Silicon Carbide under Contact Load at Room Temperature

Abstract

The room temperature onset plastic deformation and crack behavior of 3C‐SiC under contact load were investigated using nanoindentation and transmission electron microscopy ( TEM ). During loading, abrupt bursts or pop‐in in the load–displacement curves was observed at a depth of ~60 nm. The 3C‐SiC deforms elastically before the pop‐in depth, but exhibits a plastic‐elastic behavior after that. TEM observations reveal that the shear slip is the predominant deformation mechanism in 3C‐SiC during indentation. The cracks usually initiate at the intersection of shear bands or grain boundary. In addition, theoretical analysis confirms that the pop‐in event is associated with the onset plasticity of 3C‐SiC .