Researchers at Tohoku University have developed a groundbreaking titanium-aluminum (Ti-Al)-based superelastic alloy. This new material is not only lightweight but also strong, offering the unique superelastic capability to function across a broad temperature range--from as low as -269°C, the temperature of liquid helium, to +127°C, which is above the boiling point of water. This discovery holds significant potential for a variety of applications, including those in space exploration and medical technology.
Sheng Xu, an Assistant Professor at Tohoku University's Frontier Research Institute for Interdisciplinary Sciences, emphasized the importance of the alloy's wide operational temperature range. "This alloy is the first of its kind to maintain superelasticity at such an extreme range of temperatures while remaining lightweight and strong, which opens up a variety of practical applications that were not possible before. The alloy's properties make it ideal for future space missions, such as creating superelastic tires for lunar rovers to navigate the extreme temperature fluctuations on the Moon's surface."
The alloy's flexibility at extremely low temperatures makes it a promising material for applications in the forthcoming Hydrogen Society and various other industries. Of course, the alloy can be used in everyday applications requiring flexibility, such as medical devices like stents.
Currently, most shape-memory alloys--materials capable of regaining their original shape after force is removed--are limited to specific temperature ranges. The new Ti-Al-based alloy overcomes this limitation, offering wide applicability in fields that require materials with exceptional strength and flexibility, from space exploration to everyday medical tools.
The research team employed advanced techniques such as rational alloy design and precise microstructure control. By using phase diagrams, the researchers were able to select alloy components and their proportions. Additionally, they optimized processing and heat treatment methods to achieve the desired material properties.
The implications of this study extend beyond immediate practical applications. "This discovery not only sets a new standard for superelastic materials but also introduces new principles for material design, which will undoubtedly inspire further breakthroughs in materials science," Xu added.
Details of the breakthrough were published in the journal Nature on February 26, 2025.
- Publication Details:
Title: A lightweight shape-memory alloy with superior temperature fluctuation resistance
Authors: Yuxin Song#, Sheng Xu#*, Shunsuke Sato, Inho Lee, Xiao Xu, Toshihiro Omori*, Makoto Nagasako, Takuro Kawasaki, Ryoji Kiyanagi, Stefanus Harjo, Wu Gong, Tomáš Grabec, Pavla Stoklasová, Ryosuke Kainuma*
Journal: Nature
