Effect of Tensile Stress on the Transition Temperature and Current-Carrying Capacity of Nb3Sn

Abstract

The effect of a uniaxial tensile stress on the superconducting properties of a Nb₃Sn‐cored wire has been measured. The critical temperatures based on the midpoint of the resistance‐temperature curves, decrease with increasing applied stress for a niobium‐sheathed wire, while the critical temperature first increases and then decreases for a Monel‐niobium‐sheathed wire. In the Monel‐sheathed wire the initial increase in critical temperature is probably due to the fact that the Nb₃Sn is under compression. The current‐carrying capacities of both types of wire first increase, then decrease on application of stress. As much as 10% of the zero‐stress critical‐current value can be lost under tension and still be recovered on unloading.