Methods of Processing Nickel-Titanium Alloys

A method of processing at least two nickel-titanium alloys having varying compositions comprising from greater than 50 up to 55 atomic percent nickel to achieve a desired austenite transformation temperature, the method comprising:

• selecting the desired austenite transformation temperature;
• and
• subjecting the nickel-titanium alloys to similar thermal processing such that after thermal processing, the nickel-titanium alloys have stable austenite transformation temperatures, the stable austenite transformation temperatures being essentially equal to the desired austenite transformation temperature.

A method of processing a nickel-titanium alloy including regions of varying composition comprising from greater than 50 up to 55 atomic percent nickel such that each region has a desired austenite transformation temperature, the method comprising:

• thermally processing the nickel-titanium alloy to adjust an amount of nickel in solid solution in a TiNi phase in each region of the nickel-titanium alloy,
• wherein after thermally processing the nickel-titanium alloy, each of the regions of the nickel-titanium alloy has a stable austenite transformation temperature that is essentially equal to the desired austenite transformation temperature.

33-38. (canceled)

A method of processing a nickel-titanium alloy including regions of varying composition comprising from greater than 50 up to 55 atomic percent nickel such that each region has a desired austenite transformation temperature range, the method comprising:

• isothermally aging the nickel-titanium alloy to adjust an amount of nickel in solid solution in a TiNi phase in each region of the nickel-titanium alloy,
• wherein after isothermally aging the nickel-titanium alloy, each of the regions of the nickel-titanium alloy has an austenite transformation temperature range of no greater than 15° C.

42-45. (canceled)