Method for preparing rare earth permanent magnetic material by adding liquid phase nano yttrium to magnetic steel waste

Abstract

A method for preparing a rare earth permanent magnetic material by adding liquid phase nano yttrium to magnetic steel waste includes the steps that collected waste magnetic steel is pre-classified according to the classification standard that waste magnetic steel containing same rare earth elements in the same batch and same model is regarded as one category, a preprocessed magnetic material is obtained, the obtained preprocessed magnetic material is directly subjected to hydrogen decrepitation and pulverization, and rare earth hydrogen decrepitation magnetic powder is obtained; then the rare earth hydrogen decrepitation magnetic powder is sampled and analyzed, liquid phase nano yttrium is added into the rare earth hydrogen decrepitation magnetic powder according to needs to obtain mixed powder, and finally the needed rare earth permanent magnetic material is prepared through static pressing, sintering and annealing. The method effectively solves the problem that due to different melting points of components and manual operation factors, segregation of alloy ingots obtained after smelting is caused, and pre-classification is conducted so that recycling time can be saved; process steps for extracting rare earth elements are reduced; liquid phase nano yttrium is added into the rare earth hydrogen decrepitation magnetic powder, so that the use amount of neodymium and praseodymium is reduced easily, and when outside temperature changes a lot, the magnetic properties of the permanent magnetic material can be effectively kept unchanged.

Description

Technical field [0001] The invention relates to the technical field of rare earth permanent magnetic materials, in particular to a method for preparing rare earth permanent magnetic materials by adding liquid phase nano yttrium to magnetic steel scrap. Background technique [0002] In recent years, with the continuous expansion of the application field of rare earth permanent magnet materials, the demand for raw materials has increased. However, due to the high cost of rare earth mining and the increase in national regulation and control, the material cost has gradually increased. In the current situation of excessive price increases, downstream companies have relatively limited price affordability. Therefore, some downstream companies choose to use cheaper ferrite or materials such as alnico and samarium cobalt to replace the rare earth in the raw materials of neodymium iron boron magnets. , Which brings greater instability to the NdFeB magnet market. At the same time, due to t...

AI Technical Summary

Problems solved by technology

Although this process method reuses the waste magnetic steel, its extraction process is complicated, and various process parameters of the recovery container need to be adjusted according to the melting point of different rare earth elements to meet the extraction process requirements of different rare earth elements. equipment put forward higher requirements

At the same time, when processing again, a single rare earth metal oxide will be recovered, and the permanent magnet material required to be prepared will be obtained after various processes such as proportioning smelting, and the permanent magnet produced by this process has many defects. The production process is difficult to control, and there are many human factors, which will affect the quality of mass production

In addition, the permanent magnet materials produced by the existing production process have low actual coercive force, low working temperature stability, and weak corrosion resistance, which have become the main factors limiting their development and application.