Energy Dissipation in Particle Reinforced Ceramic Matrix Composites under Impact Loading

Ceramic composites have strength and friction resistance. The ability to resist failure and dissipate energy is an important property consideration in structural applications such as armor. It is well known that microstructure plays an important role in determining the strength and energy dissipation capacity. In order to tailor microstructure design, it is important to establish the relationship between energy dissipation and microstructure.

In this paper, we will present a mesoscale computational framework based on the cohesive element method (CFEM) for predicting dynamic fracture, fragmentation, contact, and interfacial friction under high-rate impact loading. The model captures the effects of microstructure constituent distribution, intergranular and transgranular fracture and friction between crack faces. The material of choice is a composite system consisting of TiB₂ reinforcement embedded in an Al₂O₃ matrix. A range of microstructure morphologies are generated and analyzed. The focus is on the fracture and frictional energy dissipation over a range of impact loading. The influences of phase size, phase distribution, constituent stiffness, and interphase bond strength are delineated. The analysis includes quantification of uncertainties arising from random variations at the microstructure level.