Computational Simulation of Matrix Microslip Bands in SiC/Ti-15 Composite

Computational simulation procedures are used to identify the key deformation mechanisms for a [0]₈ and a [90]₈ SiC/Ti-15 metal matrix composite. The computational simulation procedures employed consist of a three-dimensional finite-element analysis and a micromechanics-based computer code METCAN. The interphase properties used in the analysis have been calibrated using the METCAN computer code with the [90]₈ experimental stress-strain curve. Results of the simulation show that although shear stresses are sufficiently high to cause the formation of some slip bands in the matrix concentrated mostly near the fibers, the nonlinearity in the composite stress-strain curve in the case of the [901₈ composite is dominated by interfacial damage, such as microcracks and debonding rather than microplasticity. The stress-strain curve for the [0]₈ composite is largely controlled by the fibers and shows only slight nonlinearity at higher strain levels that could be the result of matrix microplasticity.