Processing for high permeability silicon steel comprising copper

Claim 1

IN A PROCES FOR PRODUCING ELECTROMAGNETIC SILICON STEEL HAVING A CUBE-ON-EDGE ORIENTATION AND A PERMEABILITY OF AT LEAST 1850 (G/OE) AT 10 OERSTEDS, WHICH PROCESS INCLUDES THE STEPS OF: PREPARING A MELT OF SILICON STEEL CONSISTING ESSENTIALLY OF, BY WEIGHT, UP TO 0.07% CARBON, FROM 2.60 TO 4.0% SILICON, FROM 0.03 TO 0.24% MANGANESE, FRO, 0.01 TO 0.07% SULFUR, FROM 0.015 TO 0.04% ALUMINUM, UP TO 0.02% NITROGEN, FROM 0.1 TO 0.5% COPPER AND THE BALANCE IRON; CASING SAID STEEL; HOT ROLLING SAID STEEL INTO A HOT ROLLED BAND; ANNEALING SAID HOT ROLLED BAND; COLD ROLLING SAID ANNEALED HOT ROLLED BAND; DECARBURIZING SAID STEEL; AND FINAL TEXTURE ANNEALING SAID STEEL; THE IMPROVEMENT COMPRISING THE STEPS OF ANNEALING THE HOT ROLLED BAND AT A TEMPERATURE OF FROM 1400* TO 1700*F FOR A PERIOD OF FROM 15 SECONDS TO 2 HOURS; COOLING SAID ANNEALED HOT ROLLED BAND AT A RATE EQUIVALENT TO A STEEL AIR COOL, SAID COOL INCLUDING THOSE WHEREIN THE STEEL IS COOLED IN A STATIC ATMOSPHERE OR IN A CONTINUOUS PROCESS LINE WHERE THERE IS SOME RELATIVE MOTION BETWEEN THE ATMOSPHERE AND THE STEEL, AND EXCLUDING FURANCE COOLS AND THOSE WHERE RELATIVE MOTION IS DELIBERATELY INDUCED FOR COOLING PURPOSES AND COLD ROLLING THE COOLED STEEL AT A REDUCTION OF AT LEAST 80% IN A SINGLE COLD ROLLING.