Shape Memory Alloy Electric Current
Main uses: fishing line,super elastic memory alloy mobile phone antennas,children’s toy antennas, optical glasses frames, Bluetooth headsets, earhook, medical.
Nickel-titanium alloy is a shape memory alloy. The memory alloy is a martensitic phase change alloy with very regular atomic arrangement and a volume of less than 0.5%. The amount of strain can be as high as 20%. After the stress is removed, the original shape can still be restored. This kind of deformation far beyond the elastic limit, the phenomenon that can still be restored is superelastic energy. This alloy will deform under the action of external force. When the external force is removed, it can restore its original shape under certain temperature conditions. Because it has more than one million recovery functions, it is called “memory alloy”. Nitinol shape memory alloy is a special alloy that can automatically restore its plastic deformation to its original shape at a certain temperature.
Nickel-titanium memory alloy has good processing performance and reliable product quality at the same time, its specific gravity is 80% of stainless steel; 86% of carbon steel; 75% of copper, its expansion rate is more than 20%, and the fatigue life is 1 * 10 7th power, the damping characteristics are 10 times higher than ordinary springs, its corrosion resistance is better than the current medical stainless steel, it has good compatibility with human skin, does not stimulate the skin to cause allergies, so it can meet all kinds of engineering and Medical application needs are a very good functional material. Of course, it can’t be like the human brain thinking memory, more accurately it should be called “memory shape alloy”. In addition, memory alloys also have the advantages of non-magnetic, wear-resistant, corrosion-resistant and non-toxic, so they are widely used. Scientists have now discovered dozens of alloys with different memory functions, such as titanium-nickel alloys, gold-cadmium alloys, copper-zinc alloys, etc. The shape memory alloys that have been successfully developed include TiNi-based shape memory alloys and copper-based shapes Memory alloys, iron-based shape memory alloys, etc.
1. Used in super elastic memory alloy mobile phone antennas, children’s toy antennas, optical glasses frames. With the development of the times, it has been gradually used in women’s body-shaping support rings. laboratory.
2. One-way shape recovery using one-way shape memory effect. Such as pipe joints, antennas, collars, etc.
3. External two-way memory recovery. That is to use the one-way shape memory effect and use external force to do repeated actions with the temperature rise and fall, such as thermal elements, robots, terminals, etc.
4. Super-elastic application. Such as springs, binding posts, spectacle frames, etc. The memory alloy material frame takes a spring made of memory alloy as an example. Put this spring in hot water, the length of the spring will be extended immediately, and then put into cold water, it will immediately return to its original state. The shape memory alloy spring can be used to control the water temperature of the bathroom water pipe. When the hot water temperature is too high, the “memory” function can be used to adjust or close the water supply pipe to avoid burns. It can also be made into a fire alarm device and a security device for electrical equipment. When a fire occurs, the spring made of memory alloy deforms, and the fire alarm device is activated to achieve the purpose of alarm. The spring made of memory alloy can also be placed in the heating valve to maintain the temperature of the heating room. When the temperature is too low or too high, the heating valve can be automatically opened or closed.
5. The biocompatibility of TiNi alloy is very good, and its medical examples using shape memory effect and super elasticity are quite similar. Such as thrombus filters, spinal orthopedic rods, orthodontic wires, cerebral aneurysm clips, bone plates, intramedullary needles, artificial joints, contraceptive devices, heart repair components, micropumps for artificial kidneys, etc.