A micromechanical vibration damping model of fiber-reinforced ceramic-matrix composites considering interface debonding

A micromechanical vibration damping model of fiber-reinforced ceramic-matrix composites is developed considering interface debonding. The relationship between the stress-dependent composite damping and interface debonding is established. Effects of material properties and damage-related parameters on the vibration damping of fiber-reinforced CMCs are discussed. Experimental vibration damping with interface debonding of C/SiC composites is predicted. When the vibration frequency increases from f = 1-5 Hz, the vibration damping decreases due to the increasing dynamic interfacial shear stress and low frictional dissipated energy in the debonding region. The composite vibration damping decreases with increasing fiber volume, matrix crack spacing and interface shear stress, and increases with fiber radius and fiber elastic modulus. When the interface debonding energy increases, the vibration damping decreases when the interface partial debonding and approaches the same value when the interface complete debonding, and the vibration stress for complete interface debonding increases.