Temperature Dependence of Critical Current in Nb3Sn Ribbon

Abstract
The temperature dependence of critical current in vapor-deposited Nb3Sn ribbon is measured in the temperature region above 4.2°K in magnetic fields below 55 kOe. The results of experiments are analysed by the Coffey's model. For the magnetic field of 30 kOe, the experimental values in the temperature region from 4.2°K to about 12°K agree with those calculated by the Coffey's model, but in the region above 12°K the experimental values become smaller than the calculated values. The temperature at which the experimental values deviate from the calculated values decreases with increasing magnetic field. This temperature is about 8°K in the magnetic field of 55 kOe.