Phase transformation behaviors and mechanical properties of TiNiMo shape memory alloys

Phase transformation behaviors and mechanical properties of TiNiMo shape memory alloys have been investigated. It was found that the martensite transformation temperatures decrease drastically with increasing Mo content, while the R phase transformation temperatures vary slightly. Ti50Ni49.5Mo0.5 and Ti50Ni49Mo1.0 alloys exhibit good workability with lower σy followed by drastically plastic deformation due to slip. Ti50Ni48Mo2.0 alloy with moderate martensite transformation temperature, much higher yield strength and fracture strength measured to be 589 and 799 MPa, respectively, as well as Ti50Ni48.5Mo1.5 alloy with appropriate martensite transformation temperature and excellent mechanical properties, are very promising for use as coupling materials.