INFLUENCE OF THERMOMECHANICAL TREATMENT ON FUNCTIONAL PROPERTIES OF ALLOYS WITH SHAPE MEMORY EFFECT

Abstract

One of the main factors in improving the reliability of individual components and assemblies of machines is the use of new materials with specific properties, which include superelasticity and shape memory effect. For metals and alloys with shape memory effect, heat treatment is used to ensure the required behavior of materials depending on operating conditions. (Research purpose) The research purpose is searching for the regularities of changes in the physico-mechanical properties of titanium nickelide-based alloys with the shape memory effect depending on the thermomechanical effect. (Materials and methods) Divided the materials used to carry out the planned studies in accordance with their working conditions: the property of the short-term memory effect is used for the operation of equipment and components in technical working conditions; the nature of the memory effect manifests itself for a long time or periodically repeats at the operating temperature of the equipment, that is, in working conditions. The groups of heat treatment of these materials in combination with the above-mentioned characteristics of alloys were identified. (Results and discussion) Special technological techniques have been changed to obtain the shape memory necessary for parts that do not correspond to the semi-finished product. The necessity of using heat treatment for «shape memory» was revealed. It was established that during the production of semi-finished products, if plastic deformation is applied at a temperature of at least 400 degrees Celsius, and the shape of the workpiece coincides with the configuration of the semi-finished product, heat treatment with the shape memory effect is not carried out. It has been proved that in order to stabilize the size of semi-finished products during heat treatment, annealing is carried out at a temperature of 400-450 degrees Celsius. (Conclusions) For alloys with the shape memory effect, heat treatment affects the provision of the required physical, mechanical and thermophysical properties of materials that must be used to obtain specific memory effects in specific details. For the purpose of efficient operation of shape memory alloys, heat treatment groups of this material were proposed in accordance with the required characteristics and configuration of the part.