Method for producing iron based alloy fine powder containing rare earth element and fine powder of iron based alloy containing rare earth element

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing an iron-based alloy fine powder containing a rare earth element, having reduced variation of coercivity or weather resistance and stably exhibiting high coercivity and excellent weather resistance and the iron-based alloy fine powder containing the rare earth element.SOLUTION: The manufacturing method of an iron-based alloy fine powder containing a rare earth element has a first process for pulverizing an iron-based alloy powder containing the rare earth element in a solvent containing an organic solvent and adding a phosphoric acid compound during the pulverizing to obtain a fine powder of which a surface is coated by a phosphate coating film and a second process for conducting a heat treatment on the resulting fine powder at a predetermined temperature. In the second process, the heat treatment is conducted under a temperature condition of 100°C to 300°C in atmosphere containing oxygen with partial pressure of 0.1 kPa to 5.0 kPa so that hydrogen content of the resulting iron-based alloy fine powder is 0.2 mass% or less.SELECTED DRAWING: None