Influence of Axial Pressure on Parameters of Single Pancake HTS Coil

The single pancake HTS coil (inner diameter (ID) 85 mm, outer diameter (OD) 96.5 mm, 35 turns) was investigated under axial pressure up to 12 tons in liquid nitrogen to test the influence of axial pressure on critical properties in a central plane of designed HTS double pancake–based 3 T solenoid magnet for magnetic refrigeration machine. It was shown that 15-μm thick Al2O3 oxidized coating of the aluminum disk (which was used as a heat-conducting structure) is stable (in terms of breakdown voltage and mechanical strength) with such a loading. Critical current of pancake coil does not change with axial compression up to 30 MPa pressure and starts to decrease irreversibly if P > 30 MPa. Designed axial pressure level in 3 T magnet does not exceed this permissible boundary.