Researchers from Thohok University, University of Ivate, Japanese Aerospace Agency (JAXA), Japan's National Astronomical Observatory, Tokyo City University and Kyoto University have developed an innovative copper -based alloy (With-al-ma), which exhibits a shape memory effect at extremely low temperatures, up to -200°C. Shape memory alloys can deform when cold, but return the original form when heated, similar to materials with a memory effect, such as polyurethane foam. This new alloy opens up possibilities for applications in space equipment and hydrogen technologies, where temperatures below -100°C are the norm.
Shape memory alloys based on nickel and titanium have been previously investigated (Ni-Ti) lost this ability at temperatures below -20°C, despite their practical properties. At the same time, other alloys are known, that could work at temperatures below -100°C, were not suitable for practical use. In this study, it was possible to create the first functional material for actuators, capable of generating significant mechanical energy at low temperatures. Actuators are components, which convert energy into mechanical motion, and they are not only used in space vehicles, but also in many everyday devices.
Researchers created a prototype of a mechanical thermal switch, using a Cu-Al-Mn alloy as an actuator. This device worked effectively at -170°C, regulating heat transfer by switching between contact and non-contact states depending on temperature changes. The working temperature of the alloy can be adjusted, changing its chemical composition.
Source: https://www.asiaresearchnews.com/content/new-cryogenic-shape-memory-alloy-designed-outer-space