Synergistic effect of predeformation and solution treatment: Enabling rapid processing and high strength in a Cu-15Sn-0.3Ti alloy

Abstract

CuSnTi alloy plays a crucial role as the primary raw material in preparing Nb₃Sn superconducting wires. The alloy requires a long period of solid solution treatment to eliminate segregation, increase the Sn solid solution content and improve the properties of the alloy's mechanical properties, and thus Nb₃Sn's superconducting properties, but this will causes a series of problems such as oxidation, properties degradation, and even cost. In this work, a CuSnTi alloy with a strength of 500 MPa and an elongation of 70 % was successfully developed for the first time via rotary forging combined with heat treatment. The effects of different rotary forging deformation amounts and solution times on the microstructure and properties were studied. The results show that the formation of recrystallization nuclei accelerates the diffusion of elements, thereby promoting the dissolution of the δ phase, and this in turn promotes the growth of recrystallization nuclei. The improvement of the mechanical properties of the alloy is related to grain boundary strengthening. This work improves the properties of CuSnTi alloy on the basis of saving costs and simplifying production process, and also lays a solid material foundation for the preparation of high properties Nb₃Sn superconducting wires.