Numerical modelling of a ceramic matrix composite with porous matrix phase

Abstract

To overcome the brittleness of conventional ceramics, fibre-reinforced ceramic composites have been developed in the past. The material WHIPOX®, which is developed at DLR Cologne, represents one variant of a fibre-reinforced ceramic composite that offers favourable mechanical properties for high temperature applications. Generally, the overall mechanical properties of ceramic composites are governed by their inhomogeneous microstructure. The paper describes the micromechanical modelling of WHIPOX® on several length scales: The microstructure of the matrix phase and of the fibre bundles within WHIPOX® components were recreated using parameterized numerical models and the corresponding overall mechanical properties were estimated by means of finite element analyses and periodic homogenization. Variation of the model parameters allowed studying the effect of different processing variables on the microstructure, as well as on the elastic properties. The analyses results are relevant for continuum-based finite element simulations of WHIPOX® components.