An analysis of the nonisothermal tensile test

Abstract

An analysis of the uniaxial tensile test which includes the effects of heat generation and transfer on flow behavior is presented. The analysis is based on the solution of modified versions of the onedimensional force equilibrium and heat conduction equations, subject to the appropriate boundary conditions. The stress biaxiality or triaxiality developed during necking is taken into account by including a Bridgman correction in the equilibrium expression. In order to obtain solutions of the coupled deformation-heat transfer problem, the governing equations were discretized to enable numerical calculations using a finite-difference scheme. The accuracy of the analysis was confirmed by comparison of model predictions with experimental data from nonisothermal tensile tests on 1008 aluminum-killed sheet steel. These and other simulations lead to the conclusion that temperature effects are most important following the onset of necking. The development of temperature gradients during necking can substantially decrease the tensile elongation and mitigate the stabilizing influence of positive strain rate sensitivity.