Derivation and validation of a mechanically consistent continuum damage model for brittle composite materials

Ceramic matrix composites (CMCs) combine the outstanding high temperature properties of monolithic ceramics with a quasi-ductile, non-brittle mechanical behavior. Microcracks are bridged by fibers such that damage does not directly lead to overall brittle failure. Looking at the effective properties, this microstructural damage leads to a stiffness degradation on the macroscopic scale.
Describing this stiffness degradation by a macroscopic material model is a challenging task and involves many effects such as the anisotropic damage initiation and evolution, transverse damage effects, damage deactivation under compression as well as residual (plastic) strains. On the other side, in view of an industrial application, a material model needs to be as simple as possible to enable an efficient numerical implementation as well as a straightforward and unique experimental parameter determination.