Iron nitride magnetic powder and method of producing the powder

摘要

An iron nitride magnetic powder consisting primarily of Fe<Sub>16</Sub>N<Sub>2</Sub> phase whose average particle diameter determined by particle size measurement using a TEM micrograph is 20 nm or less and whose geometric standard deviation of the particle diameter is 1.4 or less. The iron nitride magnetic powder can be obtained by a method of producing an iron nitride magnetic powder consisting primarily of Fe<Sub>16</Sub>N<Sub>2</Sub> phase includes a step of, at the time of producing an iron nitride magnetic powder consisting primarily of Fe<Sub>16</Sub>N<Sub>2</Sub> phase by subjecting a reduced powder obtained by reduction of iron oxide to ammonia treatment, using goethite containing Al in solid solution as the iron oxide.