How does Nitinol work? | 合法醫療器材資訊網

HowdoesNitinolwork?...Shapememoryalloys,suchasnickeltitanium,undergoaphasetransformationintheircrystalstructurewhencooledfromthestronger, ...

Shape memory alloys, such as nickel titanium, undergo a phase transformation in their crystal structure when cooled from the stronger, high temperature form (austenite) to the weaker, low temperature form (martensite). This inherent phase transformation is the basis for the unique properties of these alloys -- in particular, shape memory and superelasticity.

When a shape memory alloy is in its martensitic form, it is easily deformed to a new shape. However, when the alloy is heated through its transformation temperatures, it reverts to austenite and recovers its previous shape with great force. This process is known as shape memory.

The temperature at which the alloy remembers its high temperature form when heated can be adjusted by slight changes in alloy composition and through heat treatment. In the nickel titanium alloys, for instance, it can b...