Nitinol is a material with unique properties, especially its shape memory function. The so-called shape memory refers to the ability of a material to immediately return to its original shape at the corresponding temperature phase transition point after being deformed by an external force. This function is often widely used in medical devices, intelligent robots, space probes, car drives, etc. So, what makes the realization of shape memory of nickel-titanium alloy possible?
Nitinol shape memory material has the characteristics of multiphase structure, two-way shape memory effect, superelasticity and high damping. When it is bent, twisted or set to different shapes under the action of external forces, it will deform. However, when it is heated or energized, it will return to its original shape. We usually call this process "shape memory effect".
1. Austenite State：
This magical memory effect originates from a characteristic of materials science - phase change. Phase change refers to the process in which a material is transformed from one physical state to another under the action of a certain temperature, pressure, electric field and magnetic field. For nitinol alloy, its phase change is the basis of shape memory. At low temperatures, nickel-titanium alloy is in a state called "martensite". At this point, its structure presents a state of aggregation, similar to the shape of a pile of bricks. However, when the material is heated to a certain temperature, the martensite will undergo a phase change and transform into the so-called "austenite".
2. Martensite State:
When the material is in the martensite state, its lattice structure presents a more complex form, and physically presents certain bending and twisting properties. But when we heat the material according to its own phase change temperature, when the temperature rises, its internal lattice structure will change. This change process can make the lattice structure of the material more orderly. In this process, the original twisted martensite structure is stretched into a more linear austenite structure. This transformation process requires a lot of energy. The energy generated when the memory material restores its original shape is caused by the storage of this energy in the material before. Moreover, the difference between the application temperature and the rebound temperature can make nitinol have different rigidity and elasticity at different temperatures.
The shape memory effect of Nitinol comes from the unique properties of the material in different physical states, and the transformation process of physical properties under different external stimuli. Many novel technologies have been derived from the application of this technology, such as shape memory positioning to guide surgery, making the shape and movement of sports prostheses more natural, etc. In future explorations, the application of shape memory technology will be more extensive, bringing more and better innovations to people's lives. If you want to know more about nitinol, you can contact us at any time: amybai2010@zwmet.com or 0086-18161909780 (WhatsApp), we have professional technology and team to answer your questions at any time.
