High-Throughput Screening Method for Thin-Film R2Fe14B Magnet

In this article, a high-throughput screening method for thin-film magnets was proposed. Composition gradient thin films were deposited using a sputtering machine which equipped a substrate rotation and a moving mask mechanism. Local surface leakage magnetic flux was measured by a tunneling-magnetoresistance sensor continuously all over the substrate. Local coercivity on the films was estimated from the change in the leakage magnetic flux with a step-by-step demagnetization. The detailed B-H characteristics are measured using a vibrating sample magnetometer with preparing matrix composition thin films. R-Fe-B pseudo ternary composition gradient thin films were prepared and measured. In (Nd, Y, Ce)(18.5)Fe73.8B7.7 composition, the simultaneous substitution of Y and Ce for Nd achieved both high magnetization and coercivity.