Abstract

A rotating-bending fatigue testing machine was newly developed for the evaluation of the fatigue strength of a shape memory alloy wire. The rotating-bending fatigue tests were successfully performed for the TiNi shape memory alloy wire at various temperatures in water. The results were summarized as follows. If the maximum strain amplitude was in the regions of the rhombohedral-phase (R-phase) transformation, the fatigue life was longer than 107 cycles. If the maximum strain amplitude was in the region of the R-phase transformation completion and the martensitic transformation, the fatigue life became shorter as the strain amplitude increased. If the fatigue tests were performed in air, the temperature of the material rose and the transformation stress increased under cyclic deformation, yielding short fatigue life. The higher the ambient temperature, the shorter the fatigue life of the wire. The oxide film formed on the surface of the Wire did not affect the low cycle fatigue.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.