Effect of heat treatment on critical current density and n-value of (Nb,Ti)/sub 3/Sn multifilamentary superconducting wire

摘要

Studies on the relationship between n-value and heat treatment conditions of Nb/sub 3/Sn multifilamentary wires in addition to those on be are presented. The wire was manufactured in bronze process. It was heated in various conditions, then voltage-current (V-I) characteristics of each specimen were measured. In the range of the heat treatment temperature, n-value increases with temperature but J/sub c/ decreases. The properties were discussed based on the results of microscopic observation and were investigated with upper critical field (Bc/sub 2/). The results from these investigations suggest the dependence of n-value on Bc/sub 2/.