Abstract: A magnetic material and method prepares high-performance composite ferrite for a self-biased circulator. The preparation method includes: (1) preparing BaM ferrite initial powder and NiCuZnSn ferrite initial powder, respectively; (2) mixing the BaM ferrite initial powder, the NiCuZnSn ferrite initial powder and deionized water uniformly in proportion, performing ball milling in a high-energy ball mill, and then obtaining mixed powder after primary pre-sintering, secondary pre-sintering and secondary ball milling; and (3) obtaining the high-performance composite ferrite for the self-biased circulator by a low-temperature magnetic field orientation forming technology and magnetic field heat treatment.

Abstract: A device for measuring magnetism of a permanent magnet material at a high temperature includes a laser device, a power controller, a light beam controller, a temperature controller, a magnetism measurement unit, temperature sensors, and electromagnet pole heads. The electromagnet pole heads are divided into an upper piece and a lower piece for clamping upper and lower surfaces of a sample. Heat absorbing sheets are respectively fixed on front and rear surfaces of the sample. Temperatures of the heat absorbing sheets are measured by the temperature sensors. The sample is heated by laser, and the temperature controller is used to adjust a ratio of light beams of the power controller and the light beam controller irradiating the heat absorbing sheets on the front and rear surfaces of the sample, thus adjusting the temperatures of the heat absorbing sheets. The magnetism of the sample is measured using the magnetism measurement unit.

Abstract: The present invention discloses a high-resistivity sintered samarium-cobalt magnet and a preparation method thereof. According to the present invention, considering the specialty of sintered samarium-cobalt magnetic powder, fluoride or oxide is firstly prepared into nano-powder using high-energy ball milling, and the samarium-cobalt magnetic powder is prepared separately by rolling ball milling or high-speed jet milling, and then a certain electric field is applied in a fluoride suspension to drive the fluoride nano-powder to evenly cover a surface of the samarium-cobalt magnetic powder. The present invention breaks through the technical bottleneck that fluoride/oxide can improve the resistivity of a samarium-cobalt magnet but result in deterioration of the magnetic properties.

Abstract: A device for measuring magnetism of a permanent magnet material at a high temperature includes a laser device, a power controller, a light beam controller, a temperature controller, a magnetism measurement unit, temperature sensors, and electromagnet pole heads. The electromagnet pole heads are divided into an upper piece and a lower piece for clamping upper and lower surfaces of a sample. Heat absorbing sheets are respectively fixed on front and rear surfaces of the sample. Temperatures of the heat absorbing sheets are measured by the temperature sensors. The sample is heated by laser, and the temperature controller is used to adjust a ratio of light beams of the power controller and the light beam controller irradiating the heat absorbing sheets on the front and rear surfaces of the sample, thus adjusting the temperatures of the heat absorbing sheets. The magnetism of the sample is measured using the magnetism measurement unit.

Abstract: The present invention discloses a high-resistivity sintered samarium-cobalt magnet and a preparation method thereof. According to the present invention, considering the specialty of sintered samarium-cobalt magnetic powder, fluoride or oxide is firstly prepared into nano-powder using high-energy ball milling, and the samarium-cobalt magnetic powder is prepared separately by rolling ball milling or high-speed jet milling, and then a certain electric field is applied in a fluoride suspension to drive the fluoride nano-powder to evenly cover a surface of the samarium-cobalt magnetic powder. The present invention breaks through the technical bottleneck that fluoride/oxide can improve the resistivity of a samarium-cobalt magnet but result in deterioration of the magnetic properties.