Low loss electrical steel strip

Claim 1

A cold rolled steel strip useful for producing laminations having a 1.5 T (15 kG) average core loss value less than about 5.3 W/kg (2.4 W/lb.) and average peak permeability in the range 1600-1900 G/Oe. for a thickness of about 0.018 in. (0.46 m.), said cold rolled strip comprising: a composition consisting essentially of, in wt. %: ______________________________________ carbon .007 max. manganese .45-.70 silicon .8-1.1 aluminum .20-.40 phosphorus .1 max. sulfur .01 max. nitrogen .007 max. iron essentially the balance; ______________________________________ a microstructure consisting essentially of ferrite grains with an average ferritic grain size number of 3.0-4.5 ASTM; a magnetic texture characterized by a relatively large pole density of the most preferred crystallographic orientation and a relatively small pole density of the least preferred crystallographic orientation; a 1.5 T (15 kG) average core loss less than 5.3 W/kg (2.4 W/lb.) and average peak permeability in the range 1100-1300 G/Oe., for a thickness of about 0.018 in. (0.46 mm); and the capability of having an average core loss no greater than about 5.3 W/kg (2.4 W/lb.) and average peak permeability in the range 1600-1900 G/Oe., upon subsequent stamping and stress relief annealing at a temperature greater than 550° C. (1022° F.) in a non-decarburizing atmosphere, without undergoing any substantial change in grain size or magnetic texture.