Permanent magnet material low-temperature measuring device and method

The invention discloses a low-temperature measuring device and method for a permanent magnet material. Corresponding constant-temperature pole heads are arranged on pole columns, heat preservation covers are arranged on the outer sides of the constant-temperature pole heads, a J-H coil is arranged between the two constant-temperature pole heads, and a sample is arranged in the J-H coil; the output end of the J-H coil is connected with the input end of the J measurement integrator and the input end of the H measurement integrator, the output end of the J measurement integrator and the output end of the H measurement integrator are connected with the input end of the industrial personal computer, and the output end of the industrial personal computer is connected with the input end of the electromagnet electric controller. The control output end of the electromagnet is connected with the control input end of the pole, and a constant temperature unit is arranged in the heat preservation cover. The problem of acc