Patent ID: 9222145
Filing Date: 2015-12-29
Classification: B82Y,C21D,C22C,H01F

Abstract:
1. A method for producing a soft magnetic alloy ribbon having a composition represented by Fe 100-x-y-z A x B y X z , wherein A is Cu and/or Au, X is at least one element selected from the group consisting of Si, S, C, P, Al, Ge, Ga and Be, and x, y and z are numbers (by atomic %) meeting the conditions of 0<x≦5, 12≦y≦22, 1≦z≦10, and x+y+z≦25, and comprising a matrix phase in which fine crystal grains having an average diameter of 60 nm or less are dispersed at a volume fraction of 50% or more in an amorphous phase, and an amorphous layer having a higher B concentration than in said matrix phase by 0.5 atomic % or more in a region at a depth 30-130 nm from the surface of the ribbon, comprising the steps of (1) ejecting an alloy melt having said composition onto a rotating cooling roll for quenching, to form a primary fine-crystalline alloy ribbon having a matrix phase, in which fine crystal nuclei having an average diameter of 30 nm or less are dispersed at a volume fraction of more than 0% and less than 30% in an amorphous phase, said primary fine-crystalline alloy ribbon being stripped from said cooling roll when reaching a temperature of 170-350° C.; and then (2) annealing said primary fine-crystalline alloy ribbon in an atmosphere containing an oxygen concentration of 6-18 vol. %.