Sharif Digital Repository

A critical combination of matrix strain hardening exponent and fiber volume exceeded to confer tensile ductility to short-fiber reinforced metal. The bimodal distribution of tensile ductilities observed in such materials can be attributed to a transition in damage mode, from fiber fragmentation to matrix voiding. Building on results for model composites of this class and making a few specification, a simple criterion can be proposed to predict whether such composites display a low or a high tensile elongation. The results show that, composites of this class are ductile if their matrix strain hardening exponent exceeds by more than around three per cent of unity the fiber volume fraction