Dynamic strength and fragmentation of hot-pressed silicon carbide under uniaxial compression

Abstract The dynamic strength and dynamic fragmentation of a recently developed hot-pressed silicon carbide, SiC–N, has been studied experimentally using a modified Kolsky bar technique together with a servo-controlled hydraulic test machine (MTS). The effect of loading rate on the uniaxial compressive strength has been measured and further analyzed through the wing crack array approach. It is confirmed that the inertia effect is primarily responsible for the rate effect in the high loading rate regime while subcritical crack growth dominates the effect of loading rate in the low strain rate regime. High-speed photography was employed to observe and characterize in real-time the evolution of the failure mode and fragmentation during the test. Quantitative analysis of the fragments is coupled with theoretical models to investigate the mechanism involved with fragmentation over loading rates from 10−4 to 103 MPa/μs.