Fe-Co ALLOY POWDER AND PRODUCTION METHOD THEREOF, AND ANTENNA, INDUCTOR AND EMI FILTER

摘要

PROBLEM TO BE SOLVED: To provide Fe-Co alloy powder which has a high saturation magnetization &sgr;s and a controlled coercive force Hc and gives a very large μ' and a sufficiently small tanδ(μ) and is suitable for antennas.SOLUTION: In introducing an oxidant into an aqueous solution containing Fe and Co ions to form a nucleus crystal to precipitate and grow a precursor containing Fe and Co as constituents, Co in an amount corresponding to 40% of the total Co amount to be used in the precipitation reaction is added to the aqueous solution after the start of the nucleus crystal formation and before the completion of the precipitation reaction to obtain the precursor, and the dried product of the precursor is reduced to obtain an Fe-Co alloy powder. The Fe-Co alloy powder has an average particle size of 100 nm or smaller, a coercive force Hc of 52.0-78.0 kA/m and a saturation magnetization &sgr;s of 160A m/kg or higher.