CMI research at Ames National Laboratory with industry partners developed a bonded magnet without rare earths that retains magnetism at high temperatures.
Many of the industrial motors used today are induction motors. However, permanent magnet motors are generally more efficient than induction motors and can be more cost-effective in the long run, especially for factories and plants that run constantly. Currently, most permanent magnet motors rely on critical materials, specifically rare-earth based high-performance magnets, which are costly and exceed the performance needs of many industrial applications.
Scientists are working to find alternatives to rare-earth-based magnets that can function well in motors, because rare earth materials are expensive and can experience supply chain issues. However, finding a cost-effective, functional alternative material is challenging. A motor magnet needs strong magnetism that is unaffected by high temperatures and exposure to magnetic interference.
One solution was discovered by a team of researchers and industry partners led by scientists at the U.S. Department of Energy Ames National Laboratory. They developed a rare earth-free bonded magnet that not only retains its magnetism at high temperatures, coercivity nearly doubles with a 100°C (212°F) increase from room temperature.
CMI project lead Jun Cui, a scientist at Ames Lab, explains that motors can operate without magnets. “But on the other side, high efficiency motors require high-performance magnets. We are developing something in between, and offering a balanced solution: an affordable, non-rare-earth magnet for targeted industrial tasks.”
The magnet the team developed is a combination of manganese and bismuth (MnBi). The key to its performance lies in the preparation and fabrication process.
The team has already collaborated with an industrial partner to test this magnet in an industrial pump motor. The motor performed slightly better than the design specifications. The industry partners have already moved on to “fatigue tests,” where they assess the performance and endurance of the new magnet motor.
See the full story: Scientists develop rare earth free magnet for use in industrial motors