New Cryogenic Shape Memory Alloy Designed for Outer Space

A new study analyzes the use of shape memory alloys in developing thermally driven actuators for spacecraft operating space exploration missions.

Tohoku University, Sendai City, Japan

A study led by Tohoku University, Iwate University, The Japan Aerospace Exploration Agency (JAXA), National Astronomical Observation of Japan, Tokyo City University, and Kyoto University developed a novel copper-based alloy that exhibits a special shape memory effect at temperatures as low as −200 °C. Shape memory alloys can be deformed into different shapes when cold, but will revert back to their original shape when heated (as if “remembering” their default state, like memory foam). This exciting new alloy has the potential to be used for space equipment and hydrogen-related technologies, where challenging, cold environments below −100 °C are the norm.

Previously studied shape memory alloys using Ni-Ti could not maintain their shape memory ability below −20 °C, despite their otherwise practical characteristics. In contrast, the known existing shape memory alloys that can actually operate below −100 °C aren't suitable for practical implementation. This study met the challenge of finding the first functional actuator material capable of large work output at temperatures below −100 °C. Actuators are components that turn some sort of input into mechanical energy (movement). They can be found not only in machines bound for outer space, but in everyday devices all around us.