TENSILE FAILURE SIMULATION OF ALUMINA-FIBER-REINFORCED ALUMINUM MATRIX COMPOSITES

摘要

This paper examines the stress distribution around a fiber break in alumina-fiber reinforced aluminum matrix (Al{sub}2O{sub}3/Al) composites using finite element analysis (FEA) and predicts their tensile strengths using tensile failure simulations. In particular, we discuss the effect of the matrix hardening on the tensile failure of Al{sub}2O{sub}3/Al composites. First, we clarify the differences in the stress distribution around a fiber break between elastic-perfect plastic matrix and elastic-plastic hardening matrix using FEA. Second, the procedures for simulating the fiber damage evolution in Al{sub}2O{sub}3/Al composites are presented. The simulation incorporates the analytical solution to the stress distribution of a broken fiber into the spring element model for the stress analysis of the whole composite. Finally, we conduct Monte Carlo simulations of fiber damage evolution to predict the tensile strength of Al{sub}2O{sub}3/Al composites. Coupled with a size-scaling analysis, the simulated results express the size effect on composites' strengths seen in the experimental result.