On Functional Behavior of Strain-Aged Ti-Ni Alloy
The functional properties of the Shape Memory Alloys (SMA): critical temperatures, recovery strain, shape recovery rate, two-way shape memory effect (TWSME) value, residual strain etc are determined by an alloy structure which is effectively regulated by thermomechanical treatment. External training parameters strongly affect the final properties as well. The main of them are as follows: strain and loading modes, loading temperature regime (phase state under deformation), load value, loading time, number of training cycles. Actual technical and medical SME articles are functioning on bending mode in most cases. Nevertheless, the influence of external training parameters under bending on properties was not systematically studied. The present work relates to study the combined influence of structure realized under various Low- Temperature Thermomechanical Treatment (LTMT) regimes, including isothermal annealing (strain aging), and external training parameters under bending on functional properties of Ti- 50.7at.%Ni alloy. Variation of training parameters enables additional regulation of final functional properties. The obtained results can be used for development elements functioning in conditions of TWSME realization.
Pietro VINCENZINI and Stefano BESSEGHINI
E. P. Ryklina et al., "On Functional Behavior of Strain-Aged Ti-Ni Alloy", Advances in Science and Technology, Vol. 59, pp. 162-167, 2008