Recently, researchers from the Russian State University of Research and Technology first discovered the optimal parameters for the thermomechanical treatment of titanium-nickel alloys, thereby improving the technology for producing medical shape memory alloys. New methods can improve the reliability of existing surgical equipment and lead to the development of many new products.
Shape memory alloys are materials that recover their shape after being severely deformed. Currently, the most widely used shape memory alloys based on titanium-nickel alloys are used in medical implants and smart medical devices with high-reliability requirements, such as removable surgical stents or vascular stents.
The maximum index of reversible deformation of titanium-nickel alloy needs to be obtained by forming an ultra-fine grain structure through thermomechanical treatment technology at a temperature not exceeding 600 °C. However, the existing technology for producing titanium nitrite is carried out at a temperature of 800°C to 900°C, and therefore, large-scale shape memory alloys with ultrafine grain structures cannot be obtained. Researchers from the Russian State University of Research and Technology have discovered for the first time the thermomechanical processing parameters of titanium-nickel alloys, enabling large-scale titanium-nickel shape memory alloys not only to have the desired nanostructures but also to enhance their functional properties.
Viktor Komarov, a researcher at the Laboratory of Ultrafine Grain Metal Materials of the Russian National Research and Technology University, explained that the study found that 300 ° C is the boundary temperature for the transition from low-temperature deformation to high-temperature deformation of titanium-nickel alloys, while between 300 ° C and 600 ° C The shape memory properties of the deformed TiNi alloy dynamic polygonal structure reached the highest level within the range of 100 °C, and the heat treatment temperature interval was optimal for forming an ultrafine grain structure and improving the functional properties of TiNi alloy. Using the nanostructured titanium-nickel alloy obtained according to the new technique not only greatly reduces the consumption of metal, but also improves the reliability of the shape memory effect of the alloy, he said.
Viktor Komarov said that during the research, the researchers obtained the deformation map of the titanium-nickel alloy for the first time, and studied the formation process of the shape memory alloy structure at a temperature below 600 ° C, which is very important for the nanostructure of the titanium-nickel alloy. the formation is important. Analysis of the data obtained can also address the recovery, recrystallization dynamic temperature range of shape memory alloys, he said.
