The strange metal that is "both strong and flexible" makes it possible to build super-strong artificial muscles for transformable aircraft and robots!

Author: Li Chuanfu Shi Xiangqi

With the rapid development of modern science and technology, we have higher and higher requirements for the performance of materials. Especially in the fields of aerospace, robotics and artificial organs, strict requirements are placed on the strength and flexibility of materials. Recently, a scientific research team from the Frontier Institute of Xi'an Jiaotong University and the State Key Laboratory of Metal Material Strength published a breakthrough research result in the journal Nature. They successfully developed a new type of metal alloy that not only has ultra-high strength, but also has ultra-high flexibility similar to polymer materials, opening up new possibilities for the development of future technologies.

This new alloy is a unique strain glass state alloy (DS-STG) with two martensitic "seeds". It is based on Ti-50.8Ni alloy and is prepared through an innovative three-step thermomechanical treatment process. The advent of this alloy breaks the long-standing traditional concept that metal materials cannot have both strength and flexibility. In traditional materials science, high strength often means low flexibility because high strength requires strong atomic bonds, which in turn limits the material's ability to deform. However, the emergence of DS-STG alloy has achieved ultra-high strength while also having an ultra-low elastic modulus, which allows it to exhibit rubber-like flexibility in a wide temperature range from -80°C to +80°C.

This "strong and flexible" property makes DS-STG alloy have great application potential in future technological fields such as deformable aircraft, super robots, and artificial organs. For example, in the aerospace field, this alloy can be used to manufacture aircraft wings that can change shape according to flight conditions, thereby improving the performance and fuel efficiency of the aircraft. In the field of robotics, DS-STG alloy can be used to manufacture super-strong artificial muscles, making the robot's movements more flexible and precise. In addition, this alloy is also expected to play an important role in the medical field, such as being used to manufacture more flexible and durable artificial joints.

The successful development of DS-STG alloy is due to the in-depth research of the scientific research team on strain glass. Strain glass is a special amorphous alloy that presents disordered arrangement in microstructure, but can show certain elasticity and plasticity in macrostructure. The scientific research team precisely controlled the heat treatment process to form two martensitic seeds with specific orientations in the alloy. These seeds can be transformed into other phases without obstacles under stress, thus achieving ultra-low elastic modulus and ultra-large recoverable strain.

In addition, DS-STG alloy also exhibits excellent fatigue resistance. After more than 5 million cycles of loading tests, the alloy still showed no signs of fatigue failure. This property is crucial for aerospace components and robot joints that need to operate for a long time and at a high frequency.

With further research and application of this new alloy, we have reason to believe that concepts that once only existed in science fiction, such as transformable aircraft, super robots and artificial organs, will gradually become a reality. This is not only a reflection of scientific and technological progress, but also the crystallization of human wisdom.