PURPOSE: To form compressive linear strains which have an effect of forming finer magnetic domains over a long period of time without wearing projecting teeth by instantaneously applying a compressive force to the grain oriented electrical steel sheet by means of a press provided with the projecting teeth having specific shape.
CONSTITUTION: The press teeth provided to face receiving bases provided on both sides of a pass line are advanced and retreated to apply the compressive linear strains at spaced intervals to the grain oriented electrical steel sheet, by which the iron loss is decreased. The press teeth to apply the compressive force to the grain oriented electrical steel sheet mentioned above are formed as the linear projecting teeth having 20 to 3O0μm radius part in the sectional shape of the tips thereof and having no angles. The compressive linear strains having the effect of forming the finer magnetic domains are formed over an extremely long period of time in this way.
YAMAMOTO MASAHIRO
KUROKI KATSURO
YAMAZAKI TERUHIKO
