Metal with Memory
People have memories. But it’s normal for them to be able to recall things. If metals could remember, that would make the world a whole lot more amazing. This magic metal is known as the “shape memories alloy “!
The shape memory alloy (SMA) is an alloy material that has a “memory”. It is able to remember its initial form and can also sense and drive at the same moment. It’s a type of intelligent material.
The shape memory alloy will return to its original state no matter how it deforms. The action of stress and temperature can cause it to undergo phase transition. It is most important material for 4D printing due to its unique shape memory effect, pseudo-elasticity, and other properties.
Once ordinary metal is formed into a spoon it will remain that way. You can twist the spoon using pliers but it will eventually become an inutilitarian pile of metal parts. However, spoons made of shape-memory alloy can be bent and heated to restore their original shape.
There are many types of shape-memory alloys that have been found around the world. However, Nitinol has been the first to be developed, and is still the most useful.
Martensite is the SMA material with two crystal structures, austenite. One is the SMA that is heated at high temperatures, and the other is at low temperature. It is the result of the transformation from austenite into martensite that gives rise to this memory property.
The Discovery of Shape Memory Alloys
The discovery of SMA material properties is just one story. In the 1930s scientists began to study the unexpected properties of various metals. This was the beginning of early research on the material. Arne Ollander (Swedish chemist) described a pseudoelasticity phenomenon that was discovered in the study of gold-cadmium alloys. It wasn’t until 30 years later when a laboratory accident revealed that “shape memories alloy” actually existed …
The U.S. began conducting metallurgical studies in the 1960s and 1950s. Naval Weapons Laboratory. William J. Buehler (scientist) was working on casting and melting nickel-titanium rods one day. As he waited for the rods cool down, he dropped one onto the concrete floor. He heard a dull sound. After thinking this strange, he then dropped another hot nickel-titanium rod on the concrete floor. Then he heard something resembling a bell. Buehler began to worry that the casting was not going according to plan. He went to the cooler and cooled the hot nickel-titanium bar with cold water. After cooling the rod of nickel-titanium, Buehler dropped it to the ground. He heard again a dull click.
The effect was further confirmed during a meeting at the Naval Weapons Laboratory. Buehler’s assistant distributed thin strips of Nitinol, which had been bent like an accordion and folded as a comb. After Dr. David S. Muzzey grabbed the bar, he lit a lighter on it and warmed it. After a quick unfolding, the bar returned to its original form. The properties and properties that Nitinol has at different temperatures was recognized by people who called it Nitinol.
Recent and future developments show that shape memory materials don’t have to be limited only to metals. Many other types of shape memory material, including shapes memory polymers, have been created and are being used commercially.
Shape Memory Alloy
It has an array of outstanding properties that allow it to be used widely in aviation, automotive industry and medical equipment. Recently, consumer electronics have also used shape memory materials. SMA can be found in mobile antennas, as well as the AUTOfocus component of smartphone cameras.
SMA can even be used for toys and crafts. For example, flexible bracelets are made of shape-memory materials, which allow you to bend and twist them until they return to their original form.
Shape Memory Alloys
According to the National Strategic Emerging Industries Plan and other supporting policies by the Central and Local Governments, the shape memory alloy industry is one the seven new industries. The state supports and encourages it.
With the continued development of shape memories alloy technology and the reduction in cost of industrial policies to increase and promote consumer acceptance, the use of shape alloy will continue to expand.
Advanc3dmaterials (aka. Advanc3dmaterials is an advanced material. With over 12 years’ experience, Advanc3dmaterials is an established global supplier of chemical materials and manufacturer. High purity, small particles size and low impurity are the hallmarks of Nitinol that our company produces. We can help you if your requirements are lower.