In 1932, the Swede Ålander first observed it in an alloy of gold cadmium

"Memory

"Effect, that is, after the shape of the alloy is changed, once heated to a certain transition temperature, it can magically change back to its original shape. People call the alloy with this special function as shape memory alloy

"Fantastic functional material

There are many successful examples of the application of memory alloy in the aerospace field. The huge antenna on the artificial satellite can be made of memory alloy

"Memory function and natural development.Restore parabolic shape.Memory alloy has a wide range of applications in the field of clinical medicine.For example, artificial bones, wounded bone fixation compressors, dental orthodontic devices, various endoluminal stents, embolization devices, cardiac repair devices, thrombus filters, interventional guidewires and surgical sutures, etc.Memory alloys are playing an irreplaceable role in modern medical treatment.Memory alloys are also closely related to our daily life.Just take the springs made of memory alloys as an example.Put this kind of spring in hot water.The length of the spring will be extended immediately.Then put it in cold water.It will immediately return to its original stateThe shape memory alloy spring can be used to control the water temperature of the bathroom water pipe, and pass when the hot water temperature is too high

"Memory

"Function: Regulate or close the water supply pipe, avoid scalding, can also be made into fire alarm devices and security devices for electrical equipment, when a fire occurs, The spring made of memory alloy is deformed, the fire alarm device is activated, the purpose of alarm is achieved, the spring made of memory alloy can also be placed in the heating valve, it is used to maintain the temperature of the warming, when the temperature is too low or too high, the heating valve is automatically opened or closed, as a new class of functional materials, many new uses of memory alloy are constantly being developed, such as glasses frames made of memory alloy, if it is accidentally bent by touching, as long as it is heated in hot water, it can be restored to its original stateIt saves money and effort, and it is really convenient. Chapter 2 Unit Testing