Micromechanical modeling of cyclic non-closure hysteresis loops of fiber-reinforced ceramic-matrix composites considering variable matrix fragmentation density

Abstract

Cyclic loading/unloading non-closure hysteresis behavior of fiber-reinforced ceramic-matrix composites (CMCs) are investigated. Variable matrix fragmentation density upon loading/unloading is considered and incorporated into the micromechanical hysteresis loops models. Relationships between non-closure hysteresis loops, inverse tangent modulus, and interface counter slip/new slip ratio are established. Experimental non-closure hysteresis loops of different SiC/SiC composites are predicted. Effects of composite constituent and interface properties on non-closure hysteresis loops of SiC/SiC are analyzed. Due to variable matrix fragmentation density, the loading strain at peak stress is higher than unloading strain and the residual strain is much less than that of constant matrix fragmentation density.