A Study of Reactive Stresses in Ti₅₀Ni₄₀Cu₁₀ Alloy

Abstract

The study of the mechanical properties of materials based on titanium nickelide arising during thermoelastic martensitic transformations, including reactive stresses, is of great interest. The effect of generating reactive stresses in shape memory materials has an impact on various fields of technology. So, in materials with a shape-memory effect acting as mechanical energy converters and as power elements of drives, conditions are used under which deformation is fixed. This use assumes the stability of properties and operating parameters in this type of device. In this work, reactive stresses that arise in samples of alloys based on titanium nickelide when the strain is fixed, which prevents the shape-memory effect from occurring during the cycling of martensitic transformations, were studied. It is assumed that the cycling of martensitic transformations can lead to a change in reactive stresses due to the structural rearrangement of the material, which, in turn, will affect the performance of units and assemblies made of alloys based on titanium nickelide. It is shown that the level of reactive stresses developed in the sample in the heating–cooling cycle decreases in subsequent cycles. The observed hardening from cycle to cycle, under the action of reactive stresses, can characterize the phenomenon of phase hardening.