| abstract |
A high fatigue life superelastic nickel-titanium (nitinol) wire, ribbon, sheet, tubing, or the like is disclosed. The nitinol has a 54.5 to 57.0 weight percent nickel with a balance of titanium composition and has less than 30 percent cold work as a final step after a full anneal and before shape setting heat treatment. Through a rotational beam fatigue test, fatigue life improvement of 37 percent has been observed. |