Ineffective lengths in metal matrix composites

A finite element model (FEM) analysis has been conducted to evaluate ineffective lengths in metal matrix composites. The results are compared with those of a modified analytical treatment based on a previous analysis of Rosen. Ineffective lengths obtained by both treatments are in good agreement, but differ considerably from those predicted by Rosen's original formulation. The influence of different boundary loading conditions at the fiber end on the efficiency of stress transfer to the fiber has also been investigated by the FEM. In addition, an elastic-plastic FEM analysis has been used to study the influence of matrix plastic deformation on ineffective lengths. As is also discussed, the FEM approach may be useful for defining criteria for delamination at the fiber-matrix interface.