METHOD TO MANUFACTURE ND-FE-B MAGNETIC POWDER THROUGH REDUCTION-DIFFUSION PROCESS

摘要

The present invention relates to a method to manufacture ncodymium-iron-boron alloy powder. The method includes: a step of manufacturing a mixed aqueous solution including Nd metallic salt, Fe metallic salt, and boron acid; a step of manufacturing the mixed aqueous solution into initial powder through a spray-drying method; a step of manufacturing Nd-Fe-B complex oxide powder by heating and desalting the initial powder; a step of grinding and atomizing the complex oxide powder; a step of manufacturing primarily reduced complex powder by primarily reducing the atomized complex oxide powder; a step of manufacturing secondarily reduced complex powder by secondarily reducing the primarily reduced complex powder; and a step of washing the secondarily reduced complex powder. The secondary reduction of the primarily reduced complex powder is a step of mixing Ca powder and CaO with the primarily reduced complex powder and then thermally treating the mixture. In order to manufacture the secondarily reduced complex powder, as the Ca powder, as well as CaO, is added to the primarily reduced complex powder, the present invention is capable of improving coercive force by stabilizing a reduction/diffusion procedure, and thus, enabling particle atomization.;COPYRIGHT KIPO 2017