Modeling stress-dependent matrix multiple fractures of fiber-reinforced ceramic-matrix composites considering fiberoxidation and fracture

Abstract

ABSTRACT In this paper, the stress-dependent matrix multiple fractures of fiber-reinforced ceramic-matrix composites (CMCs) with fiber oxidation and fracture is investigated. The shear-lag model is combined with the fiber oxidation and fracture models, and the fiber/matrix interface debonding criterion is adopted to determine the micro-stress field of the damaged fiber-reinforced CMCs. The effects of the fiber volume, interface shear stress, interface debonding energy, oxidation temperature and time on the stress-dependent matrix multiple fractures, interface debonding and oxidation, and fiber fracture are discussed. When the fiber volume fraction and the interface shear stress in the debonding region increased, the matrix first cracking stress and saturation cracking stress increased, the saturation matrix cracking space decreased, and the matrix multiple fracture evolution rate increased. When the interface debonding energy and the interface shear stress in the oxidation region increased, the matrix cracking density increased. When the oxidation temperature and oxidation duration increased, the matrix cracking density decreased. The experimental matrix multiple fractures of unidirectional C/SiC, SiC/SiC, mini-SiC/SiC, SiC/CAS, SiC/CAS-II, and SiC/borosilicate composites are predicted.