Nonlinear energy-based relations and numerical procedure for multiaxial local analysis

In this paper, two sets of nonlinear energy-based approximate models are formulated and used to predict the local parameters in a two-phase composite system. A numerical procedure using Newton–Raphson method is developed to solve each system of nonlinear equations in small time steps. The procedure allows the estimation of the local parameters through various loading and unloading steps and therefore, is independent of a yield criterion. The local strain results obtained using the procedure are compared with experimental results obtained at the depth of circumferentially notched particulate metal matrix composite subjected to variable amplitude loads. The numerical results are in good agreement with corresponding experimental results for the geometry and load paths considered.