Method for producing large neodymium-iron-boron magnet

• Main Authors: DONG YI, LIU JIAN, HU ZHANJIANG, GONG YAFEI, YUAN WENJIE, YUAN YI, FAN YUELIN, CHEN YA
• Format: Patent
• Language: Chinese; English
• Published: 14.07.2023
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; INDUCTANCES; MAGNETS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES; TRANSFORMERS

The invention discloses a method for producing a large neodymium-iron-boron magnet, which adopts a continuous sintering furnace for sintering treatment and comprises the following steps of: pre-heating a first dewaxing chamber; conveying the green body to a first dewaxing chamber, heating to 360-390 DEG C, and preserving heat at the temperature to obtain a first product; pre-heating the second dewaxing chamber to 560 to 610 DEG C; conveying the first product to a second dewaxing chamber, and carrying out heat preservation at 560-610 DEG C to obtain a second product; pre-heating the degassing chamber to 550 DEG C to 620 DEG C; conveying the second product to a degassing chamber, heating to 820-880 DEG C, and preserving heat at the temperature to obtain a degassed product; and sintering the degassed product in a first sintering chamber, a second sintering chamber and a third sintering chamber in sequence, and then treating in an aging chamber. The coercive force and the maximum magnetic energy product of the ob