Plasma Spraying of Nd2Fe12B Permanent Magnet Materials

A major problem that exists with Nd2Fe14B permanent magnets is the high cost of fabricating complex shaped isotropic magnets. The fabrication of conventional high performance Nd2Fe14B magnetic materials involves complicated multi-step processes, such as melting, casting, homogenization, crushing, milling, magnetic alignment, pressing, sintering, and annealing. The Controlled Atmosphere Plasma Spray (CAPS) process offers the potential of near net shape depositions of magnetic materials, which can be coated with an oxidation barrier coating and then magnetized for use with little or no additional fabrication. Compared with other processes, CAPS shows a reduction in the number of processing steps and subsequently a reduced cost of processing. This project will investigate the ability of the CAPS process to fabricate isotropic Nd2Fe14B magnets with superior magnetic properties. Phase I will (1) study and optimize the deposition parameters for plasma sprayed Nd2Fe14B rare earth permanent magnets; (2) conduct compositional studies to determine the impact of rare earth substitutions for the for high performance isotropic magnetic materials; (3) study of the role of annealing in the developing and optimizing the material grain structure; and (4) evaluate the magnets to quantify the effects of deposition parameters, composition, and annealing. Both magnetic and physical properties of the processed Nd2Fe14B will be measured during the course of the research.