Nitinol Super Elastic Wire

Nitinol gets its name from its elemental composition and the discovery team who first recognized the potential of this powerful alloy (Nickel/ Titanium / Naval Ordinance Laboratory).

Nitinol alloys have the intriguing ability to recover a preset shape, even after drastic distortion. Composition is typically 55%-56% Nickel and 44%-45% Titanium, but slight adjustments of this ratio can significantly impact the properties of the material. There are two primary but overlapping categories of Nitinol. The first, known as "SuperElastic", is characterized by extraordinary kink resistance and flexibility. The second category, "Shape Memory" alloys, is valued for the Nitinol's capacity to recover a pre-set shape when heated above its transformation temperature.

Our Nitinol Wire is a SuperElastic alloy which can be strained at least eight to ten times more than ordinary spring steel without permanent deformation. It can be rather severely compressed, bent or otherwise distorted, but snaps back to its preset or "trained shape" with considerable force that can be used as work. This impressive "memory" takes advantage of stress-induced martensitic transformation.

This wire's annealed temper has a programmed straight shape, but due to its flexible properties, it can be spooled without effecting a permanent set. A new memory is imparted by restraining the material in exactly the shape required and heating to a temperature above 932°F (500°C) for a minimum of five minutes. The shape will be set upon cooling and will exhibit the same flexibility and resistance to deformation as the original wire. And it can be repeatedly retrained to achieve new shapes.

Some examples of products that use Nitinol alloys: mechanical switching devices and electronically controlled valves; robotic actuators; prosthetics; other medical instruments and implants, including stents that recover a preset diameter when body temperature is reached, keeping vessels open; eyeglass frames that, when bent, return to their preset form in hot water; shower protection devices that shut down water flow when scalding temperature is reached, allowing flow to resume when an acceptable temperature is restored.

Specifications: 56% Nickel: 44% Titanium. Straight annealed temper. Natural Oxide finish.