A new shape memory alloy will surpass titanium nickelide

Scientists at the TSU Laboratory of Physics of High-Strength Crystals, SPhTI, under a joint grant of the Russian Science Foundation and the German Research Foundation (DFG), have developed a new alloy with shape memory. Its functional characteristics surpass those of titanium nickelide, the leader among materials capable of restoring their shape when heated after high external loads. This development is promising for creating innovative solutions in the aviation, aerospace, automotive, and robotics industries.

The SPhTI scientists created, for the first time, single crystals of iron-based alloys (iron-nickel-cobalt-aluminum) with a replaceable fifth element - titanium and/or niobium. The new materials are able to compete with alloys of nickel-titanium, the most popular and sought-after compound used to create medical instruments, implants, actuators, thermal sensors, and other structures.

- New iron-based alloys are more reversible than titanium nickelide, that is, the ability to recover after deformation (shape memory effect), - says Anna Eftifeeva, a postgraduate student of the Faculty of Physics, an engineer at the Laboratory of Physics of High-Strength Crystals. - In iron-based alloys, a reversible change in shape reaches 15%, but in nickel-titanium alloys it is about 10%. Due to this, the sensors and actuators of iron-based alloys will work more efficiently, as will the mechanisms that they set in motion.

According to the head of the laboratory, Professor Yury Chumlyakov, this result was achieved with special heat treatment - a technology for which the laboratory scientists have already received a patent. Iron-based alloys are high strength. This is an important aspect for practical application in devices that must withstand high external loads, for example, in the aerospace and engineering industries. According to the developers, sensors and actuators made of a new iron-based alloy will be not only stronger but cheaper than titanium nickelide products.

The Laboratory of Physics of High-Strength Crystals SPhTI TSU is headed by professor of the Faculty of Physics Yury Chumlyakov. It is one of the leaders in creating single crystals, the basis for new materials with shape memory effect, enhanced strength, and wear resistance.

The main research areas concern the development of single crystals with thermoelastic martensitic transformations and the creation of nanocomposites based on them whose properties and structure can be controlled. Scientists at the laboratory carry out joint projects with colleagues from the USA, Germany, Spain, Hungary, China, and Japan.