Stress-strain properties of structural steel at strain rates of up to 10 5 per second at sub-zero, room and high temperatures

Abstract

A testing technique and method of processing the displacement-time data have been developed following which the stress-strain characteristics of structural steel at strain rates between 10 3 to 10 5 per second over a strain of about 50% and at different temperatures have been determined. The steel under present test condition within this strain rate range showed a strong strain rate sensitivity. The material inertia and temperature rise during high speed deformation were found to have mutually cancelling effect on the deduced flow stress. In determining the results, appropriate friction correction was also made and the results presented in this paper are all converted to those under frictionless condition. Finally, a constitutive equation has been proposed for the steel incorporating the effects of work-hardening and strain rate sensitivity of the material.