Tensile stress effects on critical current densities of coated conductors

Abstract

Tensile stress dependent critical current densities (J(c)) of two types of coated conductors, which were fabricated on a pure Ni tape and a NiCr (13 atomic %) tape respectively, were measured at 77 K, Until the stress reached certain values (K-c), the J(c) of each sample was constant, it then began to decrease as the stress was increased further. The K-c for tapes of Ni and NiCr were similar to 100 MPa and similar to 270 MPa respectively, which means K-c was enhanced almost three times for the sample fabricated on the NiCr. According to the detailed changes of voltage signals for applied currents under various stresses, the degradation process of each sample could be divided into four different regimes.