Dynamic compressive response and fracture mechanisms of ZrB2–SiC ceramic based on discrete element method

Abstract

AbstractTo investigate the dynamic compression behaviors of fracturing and damage evolution of ZrB2–SiC ceramic, this paper proposes a discrete element method to carry out the dynamic compressive behavior of ZrB2–SiC ceramic. This study is based on three‐dimensional discrete element‐finite difference coupling modeling to realize the reproduction of the splitting Hopkinson pressure bar experiment process. Micro‐parameters of the linear parallel bond model are obtained by calibrating dynamic compression strengths, stress–strain curves, and fracture characteristics of ZrB2–SiC ceramic. The dynamic compressive stress–strain curve can be divided into four stages according to the microcrack evolution and acoustic emission: stage I, linear elastic stage; stage II, microcrack initiation and then stable development stage; stage III, increment stage of microcracks before peak strength; stage IV, increment stage of microcracks after peak strength. The dynamic damage evolution with strain shows a Weibull distribution. The shape and scale parameters change with strain rate. In addition, under the dynamic compression, crack initiation stress, fracture pattern, and fragment size distribution of the ZrB2–SiC ceramic composite exhibited a significant strain‐rate dependence.