The effect of hot isostatic pressing on the strain tolerance of the critical current density found in modified jelly roll Nb/sub 3/Sn wires

The critical current density of Hot Isostatic Pressed (HIP´ed) and unHIP´ed Nb/sub 3/Sn Modified Jelly Roll wires has been measured as a function of magnetic field and of strain at 4.2 K. The reversibility of critical current density was investigated for both wires. The critical current and upper critical field were decreased for the HIP´ed sample. The reduced upper critical field of the HIP´ed wire was found to be less sensitive to strain than the unHIP´ed wire. The index (m) of the flux pinning scaling law is found to have increased from 0.86 to 2.14 as a result of the HIP processing.