Local strain fields and global plastic response of continuous fiber reinforced metal-matrix composites under transverse loading

The influence of fiber arrangement on the local plastic strain fields and t he resulting mechanical response of continuous fiber reinforced metal-matri x composites under transverse loading has been studied systematically by me ans of finite element analyses. Random, hexagonal and square fiber arrangem ents were investigated. The composite material examined consisted of isotro pic linear-elastic fibers which are perfectly bonded with an isotropic elas tic-plastic matrix with power-law hardening behavior. The random arrangemen ts were analyzed with representative material elements containing approxima tely 50 fibers. The internal strain fields are highly influenced by the fib er arrangements. Three different strengthening mechanisms are proposed for composites with perfectly plastic matrix material: the orientation, bowing- out and bending mechanisms. Simple analytical estimates are given for the o rientation and the bending mechanisms. The influence of matrix work-hardeni ng is explained by means of an effective deformable matrix volume fraction. (C) 1998 Elsevier Science B.V. All rights reserved.