Method for preparing high-performance neodymium iron boron by using secondary recycled materials

Abstract

The invention relates to a method for preparing high-performance neodymium iron boron by using secondary recycled materials, which comprises the following steps: (1) preprocessing the secondary recycled materials of the neodymium iron boron: removing impurities and dust from the secondary recycled materials and quickly drying the secondary recycled materials; (2) preparing the raw materials of the neodymium iron boron; (3) mixing materials: adding the preprocessed secondary recycled materials into the raw materials so as to form the mixed materials, wherein the weight of the preprocessed secondary recycled materials is 10-40% of the weight of the raw materials; (4) performing disproportionation reaction in a hydrogen decrepitation furnace; (5) crushing and milling by a jet mill; (6) mixing by using a double cone-type blender; (7) profiling; (8) vacuum-sintering; and (9) tempering the sintered materials: tempering at 900 DEG C for 1-3 hours for the first time, continuing to warm and tempering at 480-550 DEG C for 4-8 hours for the second time, and then performing the conventional quick air cooling, thereby acquiring a sintered magnet. The neodymium iron boron prepared by using the method is characterized in that the secondary recycled materials are used as the main ingredients, thereby saving a large amount of cost, shortening the production period, lowering energy consumption and meeting the national industrial policy. The performance of the prepared neodymium iron boron permanent magnet material can reach N42SH, and the performance index is very high.

Description

technical field

[0001] The invention belongs to the field of NdFeB permanent magnet material manufacturing, in particular to a method for preparing high-performance NdFeB from secondary recycled materials. Background technique

[0002] NdFeB is a permanent magnet material with a wide range of uses, but the current production process is relatively complicated, the cost is high, and the energy consumption is high. Especially for the secondary utilization of NdFeB scraps, there is no good method. cause greater waste. Through searching, the following four published patent documents related to this patent application were found:

[0003] 1. A method for manufacturing high-performance NdFeB permanent magnet materials (CN101877265A). This method increases the coercive force of the magnet by adding heavy rare earth element Tb to replace Dy in the raw material, and replaces Nd with a small amount of Pr to reduce production costs. The NdFeB rare earth permanent magnet material conta...