Meso-mechanical material modeling of a super plastic metal alloy is attempted. Multi-crystal grains in the metal that exibit extensive surface sliding is modeled for super-plasticity by employing a nonlinear tangential spring layer between the crystal grain and the matrix. The constitutive law for the domain in which mult-phase crystal grains of the type are dispersed is derived with the use of equivalent inclusion method on the basis of self-consistent shceme. Results of a large deformation finite element analysis on a surface cutting are shown employing Backofen's constitutive law.
