3-DIMENSIONAL ANALYSIS OF CREEP IN A METAL MATRIX COMPOSITE

A three-dimensional micro-mechanical model is used to analyze the high temperature tensile response of a short fiber reinforced metal-matrix composite. The fibers are all assumed to be aligned with the tensile axis and to remain perfectly bonded to the matrix. Analyses are carried out for fiber volume fractions of 5%, 10% and 15%. At each volume fraction, the effects of deviations from a perfectly uniform distribution are analyzed. As in previous two-dimensional calculations, staggered fiber distributions show the smallest fiber stiffening effect. The three-dimensional predictions are compared with corresponding plane strain results. For a given fiber aspect ratio and volume fraction, the trend for the dependence on clustering is the same for the two models, but there are quantitative differences, which arise largely from the different amounts of fiber overlap in the two- and three-dimensional models.