Publications Details
Strain-rate sensitivity of strength dependence on the softening factor cb in Ti-alloy wires
Jankowski, Alan F.; Chames, Jeffery M.; Brannigan, Eric M.
Titanium alloys such as Ti-6Al-4V and Ti-6Al-7Nb are widely used in the biomedical industry as structural implant materials. The strain-rate sensitivity of tensile strength is now assessed using a modified Kocks-Mecking formulation for hardening. The operative scale of the microstructural strengthening is designated by the coefficieint cb that can be determined from measurements of plastic strain, yield and ultimate strength. It is found that although that strength varies slightly with strain rate, the scale of the microstructure cb remains nearly constant for each material. Finally, a low cb-value of 14 is computed for Ti-6Al-4V that is consistent with the refined twophase microstructure needed to enhance both ductility beyond yielding and its ultimate strength.