ORIENTED ELECTROMAGNETIC STEEL PLATE

摘要

A grain oriented electrical steel sheet having a magnetic domain structure modified by strain introduction without a trace of treatment, in which noise generated when the grain oriented electrical steel sheet is used laminated on an iron core of a transformer is effectively reduced by: setting a magnetic flux density B 8 to 1.92 T or higher; then setting a ratio of average magnetic domain width of treated surface after strain-introducing treatment W a to average magnetic domain width before strain-introducing treatment W 0 as W a /W 0 < 0.4; and setting a ratio of W a to average magnetic domain width of untreated surface W b as W a /W b > 0.7; and further setting a ratio of average width of magnetic domain discontinuous portion W d in the untreated surface to average width of magnetic domain discontinuous portion in treated surface resulting from strain-introducing treatment W c as W d /W c > 0.8; and setting W c < 0.35 mm.