A lot of people are familiar with shape memory alloys. It can mysteriously revert to its original shape when heated to a specific temperature, regardless of how deformed it is.
Currently, there are dozens of types of shape memory alloys found in the world, with nickel-titanium alloy being among the most developed and widely used alloys.
Special properties of Nitinol alloy
Nickel-titanium alloy is a binary alloy composed of nickel and titanium, in addition to its unique shape memory function, it also has a series of excellent properties, is a very excellent functional material.
Shape memory properties. When exposed to external force, nickel-titanium alloy deforms at a specific temperature. Once the external force is removed, the alloy can retain its deformed shape, but can automatically return to the original shape at a higher temperature.
Superelasticity . The superelasticity of Nitinol alloy is subject to variation based on the heat treatment parameters applied, and it starts to decrease when the Nitinol alloy wire is heated over 400℃.
- Corrosion resistance. Studies have shown that the corrosion resistance of Nitinol is better than that of the best medical stainless steel at present, so it is widely used in the medical field.
Biocompatibility. Despite the fact that nickel can cause cancer, nitinol’s surface contains titanium dioxide, which functions as a barrier to prevent nickel from escaping and improve nitinol’s biocompatibility.
Good shock absorption. The superelastic Nitinol wire has an initial vibration amplitude that is just half that of the stainless steel wire.
Application of Nitinol alloy
Nitinol has been widely used in aerospace, automobile industry, medical equipment and other fields due to its excellent properties.
Automobile Industry.
The applications of Nitinol alloy in aerospace mainly include pipe joints on aircraft, as well as spacecraft antennas, fasteners, connecting parts, electrical connections and electro mechanical actuator components.
Automobile Industry.
Nitinol alloy is commonly used in automobile engine heat fan clutch, exhaust automatic adjustment nozzle, diesel engine radiator hole automatic switch and jet engine oil filter shape memory spring.
Medical Apparatus and Instruments.
Nitinol has been successfully applied in oral tooth correction, surgical correction and plastic surgery and cardiovascular minimally invasive interventional therapy. At present, there are surgical sutures, brain aneurysm clips, contraceptive rings, artificial hearts, artificial kidneys with miniature pumps and so on.
Civilian Industry Products.
Civil products mainly include super elastic glasses frames, mobile phone antennas, women’s corset brackets, high elasticity and high toughness fishing wire, headphone headsets, etc.
In recent years, nickel-titanium alloy has played an increasingly important role in many fields, but it still has some shortcomings in the actual production and processing process, such as easy oxidation, high processing cost and long production cycle. With the in-depth study of the properties of Nitinol and the continuous development of technology, the prospect of Nitinol will be better and better.