Researchers at Oak Ridge National Laboratory (ORNL) have used magnets recovered from used computer hard drives in an electric motor. The permanent magnets made from rare earth elements were reused without alteration in an axial gap motor, which can be adapted for use in electric vehicles and industrial machinery.

In work funded by the DOE Critical Materials Institute, ORNL researchers are demonstrating how rare earth permanent magnets can be harvested from used computer disk drives and repurposed in an axial gap motor. Credit: Jason Richards/Oak Ridge National Laboratory, US Dept. of Energy.

The demonstration is part of an effort to find ways to recycle rare earth permanent magnets, which are necessary for electric cars, cell phones, laptops, wind turbines and factory equipment.

The rare earth ore used to make the magnets is in high demand and mined almost exclusively outside the United States.

We’re not inventing a new magnet. We’re enabling a circular economy—putting these recycled magnets into a new package that takes advantage of their strengths while addressing a key materials challenge for American industry.

—ORNL’s Tim McIntyre

Award for CMI/Ames magnet recycling process. Seperately, researchers at the Critical Materials Institute (CMI) and Ames Laboratory invented a magnet recycling process in which magnets are dissolved in water-based solutions, recovering more than 99% purity rare earth elements. Cobalt is also recovered from cobalt-containing magnet wastes. The rare earth materials recovered have been reused in making new magnets, and the recovered cobalt shows promise for use in making battery cathodes.

The process earned a 2018 Notable Technology Development Award from the Federal Laboratories Consortium (FLC).

This technology resulted from analyzing industrially generated wastes from three US magnet manufacturing and processing companies. A US hard disk drive shredding company supplied shredded HDDs. These collaborations ensured that materials used for this research are same as those generated in real-life situations.

In addition, the Ames Laboratory Materials Preparation Center reduced the magnets from this research into metal ingots. Collaboration is on-going with a commercial partner, Infinium Metals, to produce metal ingots at larger scale.

A unique strength of this technology is that operational hazards and negative environmental impacts associated with acid-based dissolution process are eliminated without sacrificing purity, efficiency and potential economic impact, said Ikenna Nlebedim, the lead investigator for the research.