Strength prediction of composite ceramic under the non-ellipsoidal particles bridging

摘要

Purpose - This paper aims to promote a strength model for TiC-TiB2 composite ceramic with non-ellipsoidal particles bridging. Based on the microstructure of TiC-TiB2 composite ceramic, equivalent average residual stress under particles interaction is calculated with the interact direct derivative estimate. Supposing the crack opening displacement keeps ellipsoidal under the TiB2 particles bridging, crack growth resistance curve is obtained. Design/methodology/approach - Composite strength under R-cure with crack unstable propagation is calculated. Based on this model, influences of particles volume fraction, shape, size and other parameters on strength are analyzed. Findings - Results indicated that calculated values are consistent to the tested data. Crack growth resistance increases with crack propagation and TiB2 volume fraction. The TiB2 particle does not pull-out entirely even ceramic fracture. Ceramic strength increases with the TiB2 particle volume fraction, the ratio of platelet diameter and thickness, and it reduces with particle thickness. Originality/value - Supposing the crack open displacement keeps ellipsoidal under the TiB2 particles bridging, crack growth resistance curve is obtained.