Dennis W. Norwich and Audrey Fasching; Memry Corporation, Bethel, CT. Accepted for Publication, SMST-2008, Stresa, Italy, 2008.
It is a generally held belief that controlled strain fatigue life is independent of wire diameter. This has led to the widespread use of general S-N curves for Engineering metals. Independence of wire diameter on fatigue life may not hold true for Nitinol. If so care must be used when applying generic Nitinol S-N curves to product design. To provide a more comprehensive understanding of this issue, a comparison study was conducted on the fatigue properties of various diameters of NiTi (Ti-55.8/55.9 wt%Ni) wire drawn from the same starting material… Download the entire paper.