Measurement of Pure Shear Constitutive Relationship From Torsion Tests Under Quasi-Static, Medium, and High Strain Rate Conditions

Abstract Torsion tests provide important shear stress and strain relationships to reveal the fundamental plastic flow response of a material. Bespoke torsion techniques complemented by digital image correlation are developed accurately measure stress–strain relationship at quasi-static, medium rate 9/s, high above 1000/s. The equipment used includes screw-driven mechanical system, hydraulic Instron machine Campbell thin-walled tube split Hopkinson bar equipped with an ultrahigh-speed camera. A near alpha Ti3Al2.5V alloy was as model material in this study. four-camera system has been constructed monitor deformation failure during low test, gain further insight into tubular specimen. Shear exhibits noticeable sensitivity. Observations hardening evolution indicate that capacity is both dependent. High torsional shows lower hardening, compared obtained from compression present demonstrated be suitable for measurement pure constitutive relationship, including sensitivity