Strain characteristics of Nb3Sn multifilamentary wires with CuNb reinforcing stabilizer

✍ Scribed by K. Katagiri; K. Watanabe; K. Noto; K. Goto; T. Saito; O. Kono; A. Iwamoto; M. Nunogaki; T. Okada

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 547 KB
• Volume: 34
• Category: Article
• ISSN: 0011-2275
• DOI: 10.1016/0011-2275(94)90099-x

✦ Synopsis

Bronze processed multifilamentary Nb3Sn superconducting wires, with a CuNb reinforcing stabilizer instead of the conventional Cu stabilizer, were fabricated. The mechanical properties and the strain dependence of the critical current Ic were evaluated at 4.2 K and a magnetic field of 15 T. A remarkable increase in the yield stress (70%) and the plastic flow stress as compared to the values for the wire with Cu stabilizer was observed. The strain for the peak It was also increased by 0.2%. It on unloading was reversible within the strain range of 1.5%. The strain sensitivity of It in the CuNb/Nb3Sn wire was almost the same as that of the Cu/Nb3Sn wire. A decrease in the wire diameter from 0.8 to 0.5 mm resulted in a slight increase in the yield stress of the CuNb/Nb3Sn wire, but no change in the strain dependence of Ic. An increase in the heat treatment temperature from 700 to 750°C resulted in a decrease in the flow stress of 15%, but no change in the strain dependence of Ic-A marked change in the morphology of the Nb filament in the CuNb reinforcing stabilizer was evidenced during heat treatment.