Researchers at the University of Kiel in Germany have invented a new nickel-titanium-copper memory alloy that can be deformed 10 million times without breaking, while alloy materials often break thousands of times. This new material has broad application prospects in the fields of microelectronics and optical devices, sensors, medical equipment and so on.

As early as the 1960s, scientists invented the nickel-titanium memory alloy, which deforms when heated and cooled, and quickly returns to the shape determined during the initial machining. Most alloys we are familiar with will change thousands of times in two lattice states, and even crack or even break. An expert from Kiel University in Germany explained in a paper that this is because there are more and more low-temperature phases (martensite) crystal structures in the high-temperature phases (austenite) of metals. Incomplete transitions will cause the alloy to fracture. Published in the journal Science.

The memory alloy unit invented by the 邝 Te team consists of 54 titanium atoms, 34 nickel atoms, and 12 copper atoms. Researchers found that the memory alloy can withstand tens of millions of times of deformation without cracking through high-power electron microscopy and X-ray inspection at a temperature of 22 to 87 degrees Celsius. Under the microscope, when the martensite is completely transformed into austenite, two titanium and copper atoms are deposited in the crystal lattice. The deposition of titanium and copper atoms forms the basic structure of a two-phase crystal. They call this phenomenon epitaxial growth.

锌 A zinc-gold-copper memory alloy invented by James University expert James James two years ago has similar characteristics. Can withstand 16,000 cold and hot deformation without cracking. The James team's invention was published in the journal Nature.

According to "Science" magazine, the invention of Kiel University in Germany has greatly expanded the scope of application of memory alloys. Electromagnetic couplers, temperature sensors, microelectronics and optical devices, information storage media, and artificial heart valves have broad application prospects in the medical field. In addition, this memory alloy can also be used to convert thermal energy from the outside world and the environment into electrical energy, or to develop new cooling devices.