Measurements of large high-performance permanent magnet with superconducting magnet

摘要

A magnetometer with a cryogen-free superconducting magnet was developed. Sample magnetization is calculated from the induced voltage of a pickup coil under alternating magnetic fields. The sample is fixed in the superconducting magnet and the structure of the equipment is simple. When a large high-performance permanent magnet is tested, a strong magnetic force is applied on the sample. In our system, because the structure is simple, it is easy to prepare a stout sample holder that can keep the sample against the magnetic force during measurements. Cubic NdFeB magnets of about 50 and 25 mm on a side were successfully tested.