Particle reinforced MMCs with a particle size of 100 mu m and an aluminium. matrix (A16061) are analyzed by the means of automatic local deformation analysis. Two different heat treatment conditions (under- and over-aged) are investigated. It is found that the local deformation behaviour is strongly determined by particle damage. While the under-aged material shows only particle fracture, the over-aged MMC shows also particle debonding as a relevant damage mechanism.