The effect of inertia on tensile ductility

One-dimensional numerical simulations of dynamic tensile tests have been carried out over a wide range of test velocities for materials having aHollomon-typeconstitutive law with power-law strain-rate sensitivity. A variety of values of the strain-hardening exponent and strain-rate-sensitivity index have been used to analyze the effect of inertia on tensile ductility. Results show that the total elongation of the specimen is enhanced by inertia at high test velocities. This inertial effect varies with the strain-hardening exponent and strain-rate-sensitivity index and can be scaled with the normalized material density and the test velocity. Based on these results, the critical test velocity for the onset of the inertial effect as a function of material parameters has been numerically determined. To account for the effect of inertia on the enhancement of tensile ductility, a simple phenomenological explanation has been proposed.