The effect of reinforcement clustering on the steady-state creep behaviors of discontinuous metal matrix composite: A possible origin of ‘anomalously high’ stress exponent

The effect of reinforcement clustering on the steady-state creep behaviors of unidirectional SiC whisker reinforced aluminum matrix composite was investigated using finite element models with two different microstructures: Homogeneous microstructure was made up of a random dispersion of whiskers and the heterogeneous (clustered) one was idealized using hierarchical multiscale technique with 2D microstructure image of this material. Based on the numerical results, a possible mechanism for the ‘anomalously high’ creep stress exponent was proposed in the light of current knowledge.

Research highlights
► Effect of reinforcement clustering on creep behaviors of composites was analyzed.
► Clustered microstructure may attribute to higher stress exponents of composites.
► This mechanism seemed appropriate to explain realistic composite creep behaviors.
► These results should provide a means to understanding creep mechanics of composite.