Uniaxial high strain rate tension of a TiNi alloy provided by the magnetic pulse method

Abstract

This study makes use of the magnetic pulse method for providing the uniaxial tension of TiNi shape memory alloy specimens. Finite element simulations demonstrate good agreement between the evaluated residual strains and experimental values. The evaluated average strain rates are ~ 4000–5000 s−1 and in local areas, they reach 10,000–12,000 s−1. The functional properties of the alloy after magnetic pulse tension are shown and compared with the results after quasistatic tension. The values of the shape memory effect after magnetic pulse tension decrease by 15–20%. Magnetic field simulation shows that induced currents are negligible and do not lead to heating in the working part of the specimens. It is concluded that the reason for the decrease in the shape memory effect is the high pre-strain rate. Reorientation processes must be sensitive to the strain rate, so the proportion of the oriented martensite decreases with increasing strain rate.