When it comes to shape memory alloy, many people have heard of its name. No matter how deformed it is, after heating to a certain temperature, it can magically change back to its original shape.
So far, dozens of shape memory alloys have been found in the world. Nitinol is one of the earliest developed and most practical alloy materials.
Nitinol is a binary alloy consisting of nickel and titanium. In addition to its unique shape memory function, it also has a series of excellent properties, is a very good functional material.
1.Shape memory characteristics.
Nitinol alloys are deformed by external forces at a certain temperature. After the external force is removed, the shape of the deformation can still be maintained,but at higher temperatures can automatically return to the original shape.
The superelastic energy of nitinol varies with the heat treatment conditions. When the nitinol wire is heated to more than 400℃, the superelasticity begins to decrease.
Studies have shown that the corrosion resistance of nitinol alloy is better than the best medical stainless steel, so it is widely used in the medical field.
Although nickel has a carcinogenic effect, but titanium dioxide on the surface of nitinol acts as a barrier, can inhibit the release of nickel, nitinol alloy has good biocompatibility.
5.Good shock absorption.
The initial vibration amplitude of the superelastic nitinol alloy wire is only half that of the stainless steel wire.
A series of excellent properties of nitinol alloy makes it widely used in aerospace, automotive industry, medical equipment and other fields.
Nitinol in aerospace applications include aircraft pipe joints, as well as spacecraft antennas, fasteners, connectors, electrical connections and electromechanical actuators.
Nitinol alloy is commonly used in automotive engine heatproof fan clutch,automatic exhaust adjustment nozzle, automatic opening and closing of diesel engine radiator hole, jet engine oil filter shape memory spring.
Nitinol has been successfully used in oral orthodontics,surgical correction and plastic surgery, as well as cardiovascular minimally invasive interventional therapy. At present, surgical sutures, brain aneurysm clips, contraceptive rings, artificial hearts, artificial kidneys with micro-pumps have been put into clinical trials.
Civilian products include super elastic eyeglass frame,mobile phone antenna, women’s bra bracket, high elastic and toughness fishing line, headphone headgear and so on.