High-Temperature Deformation of a Granulated Nickel Alloy

A variant of thermoviscoplasticity theory is proposed, by mathematical modeling of the viscoplastic behavior of a granulated nickel alloy under high-temperature conditions and based on flow theory with combined hardening. The variant of thermoviscoplasticity theory is generalized to nonisothermal loading and the dependence of the loading process on the strain rate. The results of experiments on uniaxial tension for cylindrical samples of a granulated nickel alloy at high temperatures and various strain rates are presented. The calculated viscoplastic strain diagrams are compared with experimental ones. Satisfactory agreement between the calculated and experimental results is observed, which indicates the adequacy of this variant thermoviscoplasticity theory and the method for identifying the material parameters.