From the summary: Micromechanics-based models are considered for application to viscoplasticity and damage in metal matrix composites, considering piecewise uniform eigenstrains in each material phase. Standard applications of the method to a two-phase model (only one sub-volume per phase) deliver too stiff responses. Thus, we propose two modifications that improve considerably the overall stress-strain response, at least for materials sustaining a linear hardening under large strains. We also introduce damage effects in the method, using two modeling approaches: the “direct simplified model, using only two damaged phases, and the “generalized eigenstrain model”, with more degrees of freedom, that allows the description of interfacial damage.