Mehanical Behavior of Metal Matrix Fiber Composities with Fiber-Matrix Interfacial Failure and Slide under Longitudinal Shear Loading.

Abstract

Mechanical behavior of a metal matrix fiber composite under longitudinal shear loading is considered by means of a homogenization theory. The microstructure of the composite is assumed to be periodical array of fibers and associated hexagonal unit cells are placed in the composite. Displacement of the composite is described as two-scale asympotic expansion to observe the macroscopic and microscopic fields separately. On the basis of the homogenization theory, elasto-plastic analysis is made with the unit cell of the composite. The interface between fiber and matrix is modeled as a perfect bond before the interfacial failure and as a frictional contact with slide after the interfacial failure. This method is applied to a SCS6/Ti-6A1-4V metal matrix composite. The nonlinear constitutive behavior of the composite and microscopic stress distribution are shown with variation of the coefficient of the friction on the interface.