High-strain-rate deformation and comminution of silicon carbide

TLDR: In this article, the microstructural differences affected the microcracks propagation: either intergranular or transgranular fracture was observed, depending on the processing conditions, and the spacing between shear bands and the shear displacement within the shears were not significantly affected by the microstructure.

Abstract: Granular flow of comminuted ceramics governs the resistance for penetration of ceramic armor under impact. To understand the mechanism of the granular flow, silicon carbide was subjected to high-strain, high-strain-rate deformation by radial symmetric collapse of a thick-walled cylinder by explosive. The deformation, under compressive stresses, was carried out in two stages: the first stage prefractured the ceramic, while a large deformation was accomplished in the second stage. The total tangential strain (−0.23) was accommodated by both homogeneous deformation (−0.10) and shear localization (−0.13). Three microstructures, produced by different processing methods, were investigated. The microstructural differences affected the microcrack propagation: either intergranular or transgranular fracture was observed, depending on the processing conditions. Nevertheless, the spacing between shear bands and the shear displacement within the shear bands were not significantly affected by the microstructure. Within...