Non-oriented magnetic steel sheet with excellent punching workability

Abstract

A non-oriented electrical steel sheet with low iron losses and excellent blanking property is provided that has a composition of components including, in mass%, C: 0.0050% or less, Si: 2.5 to 6.5%, Mn: 0.05 to 2.0%, P: 0.10% or less, S: 0.0050% or less, Al: 0.30 to 2.0%, N: 0.010% or less, Pb: 0.00010 to 0.010%, and Zn: 0.0005 to 0.020%, in which the ratio [Zn] / [Pb] of the Zn content (mass%) to the Pb content (mass%) is 1.58 or greater, and provided that the particle size distribution of secondary-phase particles in the particle size range of 0.10 µm or greater but less than 5.00 µm in a cross-section of the steel sheet in the thickness direction that coincides with the rolling direction is represented by a histogram where each class represents the particle size, the frequency represents the number density, and the class interval is 0.10 µm, the force of pinning magnetic domain walls calculated with Expression (3) below: ∑i=1nπdiNSi , where di represents the class value (µm) of a class i, and Nsi represents the frequency (number / µm2) of the class i) from the particle size distribution is 0.0015 or less.

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