Mechanical anisotropy and ideal strength in a multifunctional Ti–Nb–Ta–Zr–O alloy (Gum Metal)

Abstract An ideal shear strength of Gum Metal, a newly developed set of beta-type titanium alloys with the nominal composition Ti-24(Nb + V + Ta) – (Zr, Hf) – O (at.%) believed to deform without motion of crystal dislocations, has been investigated experimentally for precise determination. Tensile tests of single crystals of Gum Metal along the , , and directions showed that the Young' moduli were 40, 60, and 86 GPa, respectively. The elastic constants were estimated as c11 – c12 = 25 – 27 GPa and c44 = 29 – 36 GPa. In terms of these values, the anisotropy factor and the ideal strength were evaluated as 2.3 – 2.6 and 1.7 – 1.9 GPa, respectively. It was found that a ratio of the actual ultimate tensile strength to the ideal strength for Gum Metal was much higher than for other bcc metals.