On low cycle fatigue in metal matrix composites

A numerical cell model analysis is used to study the development of fatigue damage in aluminium reinforced by aligned, short SiC fibres. The material is subjected to cyclic loading with either stress control or strain control , and the matrix material is represented by a cyclic plasticity model, in w hich continuum damage mechanics is incorporated to model fatigue damage evo lution. This material model uses a superposition of kinematic and isotropic hardening, and is able to account for the Bauschinger effect as well as ra tchetting, mean stress relaxation, and cyclic hardening or softening. The c ell model represents a material with transversely staggered fibres. With fo cus on low cyclic fatigue, the effect of different fibre aspect ratios, dif ferent triaxial stress states, and balanced as well as unbalanced cyclic lo ading is studied.