Modeling for cyclic loading/unloading hysteresis loops of carbon fiber-reinforced ceramic-matrix composites at room and elevated temperatures. Part I: Theoretical analysis

The hysteresis loops models of fiber-reinforced ceramic-matrix composites (CMCs) are developed based on the Coulomb friction law instead of a constant frictional shear stress usually assumed in hysteresis analysis. Based on damage mechanism of fiber slipping relative to matrix upon loading/unloading, the interface slip lengths are obtained by fracture mechanics approach. The effects of matrix stochastic cracking, fiber volume fraction, interface debonded energy, interface frictional coefficient and fiber Poisson ratio on hysteresis loops, interface slip lengths and interface slip stresses have been analyzed.