The melt spinning process is used to recycle permanent magnets. For this, the material is melted in a crucible using an induction coil and subsequently poured onto a copper wheel. (© Fraunhofer Project Group IWKS)

The latest generation of electric motors is increasingly being equipped with strong, multi-ton permanent magnets instead of a gearbox. The most powerful magnets are based on neodymium, iron, and boron. Dysprosium is also frequently contained. But while iron and boron are readily available, the supply of neodymium and dysprosium is critical. Therefore, scientists are trying to recycle magnets. Up until now, this meant extracting the rare earth elements from the magnets again.

Instead of trying to regain each individual type of rare earth, the entire material is recycled – meaning the complete magnet. For recycling, the scientists rely on the melt spinning process – a method already tried and tested for other alloys, also known as “rapid solidification.”

In many cases, the magnets are extremely difficult to remove from the engines, so ways of creating a collection cycle for used engines is in development, as well as a design more suitable for disassembly that would allow engines to be alternatively designed to make it easier to remove the magnets.