Rare Earth Magnet Recycling

About

What is the problem? Rare earth magnets are used in a wide range of commercial devices, Rare earth metals have become increasingly expensive over the last few years and supplies can be difficult to access. There are currently no efficient methods to remove these magnets from redundant or broken products.   Our new Solution? A system that allows simple extraction using hydrogen decrepitation.   Benefits of the new technology Efficient easily scalable removal method, results in de- magnetized powder ready for re-refining  or potential re incorporation into magnet manufacture.   Background Hydrogen decrepitation is a well known process for breaking rare earth alloys (e.g. Nd Fe B) into powder. Hydrogen preferentially enters the rare earth rich grain boundaries in the material with an associated volume expansion. The structure cannot cope with such a large volume expansion and the grains break away from the material forming a fine powder. In this process hydrogen is introduced into an evacuated chamber filled with assemblies, such as hard disk drives, containing rare earth magnets. In the case of hard disk drives it is beneficial to first break open the assembly to expose the magnets prior to decrepitation.  A safe mixture of hydrogen and inert gas at low pressure will then cause the magnets to decrepitate within a few hours. The de - magnetized alloy can then be simply removed by screening.