Particle fracture in high-volume-fraction ceramic-reinforced metals: Governing parameters and implications for composite failure

摘要: Abstract Weibull parameters of angular alumina particles are determined from experimental tensile test data on high-ceramic-content metal matrix composites using a micromechanical model that accounts for internal damage in the form particle cracking, dominant mode these composites. The fraction broken is assessed drop Young's modulus and fracture assumed to be stress controlled. Two extreme load-sharing modes, namely purely local global mode, considered account load redistribution due fracture. Consistent powder strength can thus “back-calculated” embedded different Al–Cu matrices. On other hand, this calculation fails pure Al composites, which exhibit much larger strain failure than It shown role plastic (composite) constitutes second parameter governing damage. This finding rationalized by particle–particle interactions tightly packed ceramic particle-reinforced increase heterogeneity brought with increasing strain. Failure alloyed well described (lower bound) model, predicts catastrophic an avalanche same aluminium occur at onset instability, also agreement results once accumulation accounted for.