Numerical Modelling of Particle Distribution Effects on Fatigue in Al-SiCp Composites

Finite element analysis has been used to study the effects of clustering on fatigue crack growth behavior in Al-SiCp composites. Consistent differences were identified between models with regular vs. clustered particle arrangements in terms of crack path morphologies and local crack-tip stress intensity fluctuations. Furthermore, predicted influences of clustering on growth rates in the numerical models were found to be consistent with previous experimental results (i.e., growth rates rose with increased clustering) demonstrating that load transfer effects associated with changes in particle distribution may play a direct role in controlling the growth of short cracks in these materials. (CSA)