In this talk, we will investigate a PDE system which couples phase separation, elasticity and damage processes. The system is considered on a Lipschitz domain with mixed boundary conditions for the elastic deformations. We will introduce a suitable notion of weak solutions consisting of weak formulations of the diffusion and the momentum balance equation, a variational inequality for the damage process and an energy inequality. The main aim is to prove existence of weak solutions and to investigate the degenerate limit where complete damage may occur. This is a joint work with Christiane Kraus.