Overview of an Experimental Program for Development of Yield Surfaces Tracing Method

This paper develops an experimental technique to evaluate the initial yield surfaces of metallic materials, as well study their evolution during plastic flow. The tracing is necessary for deriving and calibrating more robust phenomenological models directional distortional hardening. Such can be used characterize behavior structures experiencing complicated demanding loading modes, such multiaxial ratcheting. developed in this work uses thin-walled tubular specimens, along with a servo-hydraulic machine, under various modes tension/compression torque. Identification onset flow based on small proof equivalent strain evaluated from outputs contact biaxial extensometer firmly attached specimen surface. allows evaluation both surface, theevolved surface after prestrain. Throughout test, continuous fully automatized elastic moduli assured through algorithms written C# language. current shown provide promising results effectively capture conventional materials.