Direct Synthesis and Optimization of Rare Earth Transition Metal Permanent Magnet Systems.

Abstract

Abstract : Special sputtering methods have been used to synthesize rare earth transition metal films such as SmCo5, Nd2Fe14B, and several new compounds in the Sm-Ti-Fe system. Films have been synthesized with different crystal textures by varying the sputtering conditions. The magnetic properties observed have been found to be strongly dependent on the film texture. For example, SmCo5 films with a (200) texture exhibit intrinsic coercive forces, of 8 kOe, while (110) textured films show values of about 18 kOe. For the Nd2Fe14B compound films have been made which exhibit an easy axis of magnetization either in the film plane or out of the flm plane depending upon the crystal texturing of the films. In the film plane static energy products up to 21 MG-Oe have been observed in as sputtered films without any subsequent heat treatments in certain rare earth transition metal systems. For films containing only Sm, Ti, and Fe room temperature coercive force values up to 24 kOe have been observed. Films have also been made such that the magnetic properties are highly anisotropic in the plane of the film for certain amorphous systems. The incorporation of the coercive force magnetic films that have been sputter synthesized into several types of micron scale device geometries has been considered.