Original paper(Vol.50 No.3 pp.198)

Impact Tensile Strength of Aged Titanium Alloys

Kinya@OGAWA

Abstract:Since titanium alloy is one of the most promising structural materials for the high velocity vehicles such as aircrafts and automobiles, the impact tensile strength of the material at various temperatures is presently investigated. Three kinds of aging treatments were performed on the beta-titanium alloy, and the stress strain relations were identified in the wide range of the temperature from 77K to 573K, and the strain rate from 10-3S-1 to 103S-1. Thermally activated process concept was applied to explain the temperature and the strain rate effect on the flow stress, and the stress-strain relations at high strain rates were well understood by the concept with taking account of adiabatic heating effect during deformation. The stress strain curves depend on the microstructures produced by the different aging treatments, while the temperature and the strain rate effects are almost identical for the materials investigated.

Key Words:Impact, Titanium alloy, Aging condition, Split-Hopkinson bar, Adiabatic heating, Thermally activated process, Stress-strain relation