Synergistic effects of interface slip and fiber fracture on stress-dependent mechanical hysteresis of SiC/SiC minicomposites

In this paper, the synergistic effects of interface slip and fiber fracture on stress-dependent mechanical hysteresis of SiC/SiC ceramic-matrix minicomposites (mini-CMCs) are investigated. Upon cyclic loading/unloading, the relative slip between the fiber and the matrix, and the fracture fiber affect the hysteresis behavior of mini-CMCs. The micro-stress field of the damaged mini-CMCs is obtained through shear-lag analysis, and cyclic loading/unloading hysteresis strain is related with the stress level, interface slip, and broken fiber. The effects of constituent properties and internal damage state on cyclic loading/unloading interface slip and hysteresis loops of SiC/SiC minicomposite are analyzed. The experimental matrix cracking density, stress-dependent mechanical hysteresis and interface slip of Hi-Nicalon(TM), Hi-Nicalon(TM) Type S, and Tyranno(TM) ZMI SiC/SiC minicomposites are predicted. The interface debonding and slip range, and mechanical hysteresis loops of SiC/SiC minicomposites are affected by the stress level, constituent properties of the fiber volume, interface properties, and damage state of matrix cracking and broken fiber subjected to cyclic tensile loading.