Patent ID: 8097094
Filing Date: 2012-01-17
Classification: C21D,C22C,H01F

Abstract:
1. A high strength non-oriented electrical steel sheet characterized by consisting essentially of, by mass %, C: 0.06% or less, Si: 3.1 to 3.5%, Mn: 0.5 to 1.2%, P: 0.30% or less, S or Se: 0.040% or less, Al: 0.005% or less, Cu: 0.6 to 8.0%, Cr: 4.5% or less, N: 0.0031 to 0.0301%, and a balance of Fe and unavoidable impurities, said steel sheet having an average crystal grain size of 30 to 300 μm by holding the steel sheet in a heat treatment at 800° C. to 1100° C. for 20 seconds to 5 minutes and containing a metal phase comprised of Cu having a diameter of 0.1 μm or less and a number density of 20 /μm 3 or more in the steel sheet by holding the steel sheet in a heat treatment at a temperature range of 300° C. to 650° C. for 5 seconds or more.