A method for preparing neodymium-iron-boron by regeneration of waste materials containing neodymium-iron-boron

Abstract

The invention provides a method for preparing neodymium iron boron through regenerating a waste material containing neodymium, iron and boron. The method comprises steps of (1) preprocessing the waste material; (2) correcting the components of the waste material; (3) crushing by hydrogen; (4) preparing into powder; (5) molding under a magnetic field; and (6) vacuum sintering. The method fully uses the waste material recycled in a production process, has high recovery rate of the waste material, can produce high performance product, has a simple and controllable flow, has high operability, uses no strong acid and strong base polluting the environment, is environment-friendly and energy-saving, and has high social and economic benefits.

Description

technical field [0001] The invention relates to the field of metallurgy, in particular to a method for reproducing neodymium-iron-boron waste materials containing neodymium-iron-boron. Background technique [0002] NdFeB has the title of "a generation of permanent magnet king". It has excellent comprehensive magnetic properties and is widely used in electronics, automobiles, medical care, environmental protection and energy saving, aerospace and other industrial fields. According to incomplete statistics, the global output of NdFeB permanent magnets reached 110,000 tons in 2011, and has maintained a high growth rate of more than 20% in the last ten years. [0003] With the upgrading and scrapping of electronic devices, automobiles and other instruments and equipment, a large amount of NdFeB waste will inevitably be produced. The proportion of waste materials can be as high as 15-30%. If they cannot be effectively treated, these materials and the rare earths in them can only...

AI Technical Summary

Problems solved by technology

[0004] In the prior art, as reported in the literature, Liu Mingqing and others roasted and dissolved the NdFeB waste materials by the hydrochloric acid excellent solution method, and then re-separated them into rare earth oxides, and then prepared the metals required for magnet production through metal smelting. The process is cumbersome, the process is long, and the manufacturing cost is high

Chinese patent 95101204.5 introduces a method of producing NdFeB by remelting waste materials. This method produces a large amount of slag, the process is complicated, the yield is low, and the practical value is poor.

This method still has many problems in the implementation process of the waste pretreatment process, such as oily materials, small-sized materials, etc., which are difficult to clean; after the treatment, it is necessary to increase the process of remelting and homogenization, and only a small amount can be added to the new waste. Among the materials, the recycling rate is not high, the magnetic properties of NdFeB are not good, and the practical value is limited.

Images