Metallic glass materials could help drones fly longer on less power

Researchers at Saarland University in Germany, led by Professor Ralf Busch, are developing metallic glass materials to improve the efficiency of electric motors used in drones, e-bikes, and household electronics. Conventional motors suffer from energy losses known as "iron loss," caused by internal friction when magnetic fields repeatedly reverse direction in crystalline iron alloys. Metallic glasses, which have a disordered atomic structure rather than an ordered crystal lattice, reduce these losses significantly because their magnetic regions can reorient more easily during magnetization cycles. The team focuses on soft magnetic alloys containing 70 to 80 percent iron, designed to remain amorphous and avoid crystallization during manufacturing. They employ metal 3D printing to produce motor parts layer by layer from powdered metallic glass, carefully controlling cooling to maintain the amorphous structure. Unlike typical glass, metallic glass is strong and not brittle. After testing hundreds of alloys, the researchers identified three suitable candidates compatible with 3D printing and possessing the desired magnetic properties. This work is