Mechanical Property of Ti-Ni Superelastic Wire Ropes

Abstract

Recent years, a few companies made Ti-Ni superelastic wire ropes. The advantages of Ti-Ni superelastic wire ropes are high damping capacity, long fatigue life, and large bending flexibility and large responsively. The aim of present study is to investigate the effect of design of the wire rope on stress hysteresis, superelastic strain and dissipated strain energy by using tensile tester. The shape of wire rope was 3x0.1 mm (3-strand wires), 3x0.14 mm, 3x0.2 mm, 7x0.1 mm (7-strand wires), 7x0.14 mm and 7x0.2 mm. Transformation temperatures were measured with a differential scanning calorimeter (DSC). The mechanical properties were measured by tensile test at 25 ̊C. Larger stress hysteresis and dissipated strain energy were observed for the wires with large diameter. The stress of stress induced martensitic transformation and hysteresis were increased with increase the number of wires in Ti-Ni wire rope. It was found that the best specimen to absorb vibration was the 7-strand wire ropes with a diameter of 0.2 mm.