Asymmetric Motor Advantage for Army Through Novel Magnetic Coating

Magnet coatings can significantly improve thermal properties in electric and hybrid motors, however current coatings such as nickel or zinc are used for corrosion and oxidation resistance rather than enhancing thermal management. As a result, Vulcan Elements has identified high potential materials (i.e., iridium, tungsten carbide and yttria stabilized zirconia (YSZ)) that can optimize thermal properties at increased motor torque and speed. The identified coatings have been proposed due to their utilization in high temperature applications such as hypersonics, paramagnetic properties (i.e., they will not interfere with the magnetic properties of the magnet), as well as their thermal conductivity 100W/mK+ (except for YSZ, which absorbs thermal energy, a necessity for thermal signature control). Ultimately, our work will quantify how a novel magnet coating can increase an electric motor’s torque and speed at temperatures above 180 degrees C without compromising the magnetic properties that allow for reduced size and weight. This effort will build on current neodymium-iron-boron (NdFeB) based electric motors which show improved performance in size and weight when required to maintain similar high power (700+ HP) and torque requirements (15,000+ ft-lb). Our work will also build on the current disadvantage of NdFeB magnets in high temperature environments as compared to heavier, less efficient rare earth free magnets.  Creating novel coating solutions for NdFeB magnets will provide Army with an asymmetric motor advantage that allows new vehicles to achieve higher power and torque performance with reduced weight and size. Furthermore, the ability to identify the coating that maximally reduces the amount of thermal signatures will help improve the stealth ability of permanent magnet motors which are a common weak point for vehicles operating under stressed conditions.