Magnetic field stability of PrFeB magnets developed by GBD for cryogenic permanent magnet undulators

Fig. 2 illustrates the magnetic properties of the PrFeB magnets with and without GBD. The Br was approximately 13.85 kGs, and there were no obvious changes observed. However, the Hcj of the PrFeB magnets with GBD displayed a large increase in different degrees. The smaller orientation direction thickness of the magnet resulted in a larger increase of the Hcj. The comprehensive magnetic properties of the PrFeB magnets is about (BH)max + Hcj = 74.7.86