Fabrication and Test of HTS Magnet for Induction Heating Device in Aluminum Extrusion Processing

This paper reported the fabrication and the test results of the high temperature superconducting (HTS) magnet developed for the aluminum billet heater for aluminum extrusion processing. In this magnet, the HTS coils were combined with iron cores, because the required magnetic field in the working region was about 1T. Two HTS coils wound directly on the convex shape iron cores were fabricated. The HTS coils were made by the no-insulation winding of REBCO tape with the YOROI-coil technique. Each of them was separately installed in an individual cryostat. Two HTS coils with iron cores were disposed oppositely to each other and were magnetically connected by a C-shape yoke placed in room temperature. The HTS coil was cooled down to about 15 K by the GM cryocooler in the initial cooling. The magnetic field of 1.06 T at the center of the heating region was stably generated with the rated current of 200 A. It was also demonstrated that the HTS magnet could be charged up to 300 A without quench. According to the observation of the electromagnetic force direction from the outside of the cryostat, it was confirmed the validity of the force balance design of the magnet.