Ni-free beta Ti alloy with shape memory and superelastic properties

摘要

A group of substantially nickel-free beta-titanium alloys has shape memory and superelastic properties suitable for medical device applications and the like. In particular, the present disclosure provides a family of titanium-based alloys comprising 16-20 at% hafnium, zirconium or a mixture thereof, 8-17 at% niobium, and 0.25-6 at% tin. This alloy family exhibits a recovery strain of at least 3.5% after axial, bending or torsional deformation. In some instances, these alloys have a strain recovery of greater than 5%. Niobium and tin are provided to the alloy to control the stability of the beta phase, thereby enhancing the ability of the material to exhibit shape memory or superelastic properties at the desired application temperature (eg, body temperature). Hafnium and / or zirconium can be added interchangeably to increase the radiopacity of the material and also contribute to the superelasticity of the material. [Selection] Fig. 4