Effect of axial strain cycling on the critical current density and n-value of ITER niobium-tin wires

摘要

Measurements have been made of the effect of axial strain cycling on the critical current density and n-value of two ITER candidate niobium-tin wires (Europa Metalli-LMI (EM-LMI) and Vacuumschmelze). The wires were subjected to similar to1300 strain cycles to incrementally increasing applied tensile strains, with 100 cycles per 0.056% increment. For both wires, there were no changes in the critical current density or n-value for the similar to500 cycles up to 0.282% applied strain (except for the first cycle of the EM-LMI wire). Cycling to higher applied strains (0.339-0.677%) caused the critical current density and n-value to incrementally increase at all applied strains, with the critical current density eventually increasing by 5-7% at 12 T and zero intrinsic strain. Cycling to applied strains above 0.677% (similar to0.4% intrinsic strain) damaged the wires. (C) 2003 Elsevier B.V. All rights reserved. [References: 13]