Use of silicon steel alloy having a critical sulfur range to insure cube-onface orientation

Claim 1

IN THE PROCESS OF PRODUCING A MAGNETIC SHEET HAVING A HIGH PERCENTAGE BY VOLUME OF GRAINS HAVING A (100) (001) ORIENTATION FROM AN IRON-SILICON ELECTRICAL STEEL ALLOY HAVING A SMALL AMOUNT OF SULFUR THEREIN AND SMALL AMOUNTS OF IMPURITIES INCLUDING OXYGEN, WHEREIN THE STEPS OF THE PROCESS COMPRISE, (1) HOT ROLLING AN ALLOY SLAB TO STRIP FORM, (2) ANNEALING THE HOT ROLLED STRIP, (3) COLD ROLLING THE STRIP TO SHEET FORM, (4) INTERMEDIATE ANNEALING THE STRIP BETWEEN SUCCESSIVE COLD ROLLING STEPS, AND (5) FINAL ANNEALING THE STRIP TO PRODUCE SECONDARY RECRYSTALLIZATION, THE IMPROVEMENT COMPRISING CONDUCTING THE FINAL ANNEAL SO AS TO SUBJECT THE FINAL COLD ROLLED SHEET, CONTAINING OXYGEN IN AN AMOUNT BELOW 0.0035%, BY WEIGHT, TO A FINAL ANNEALING TEMPERATURE OF BETWEEN 1100*C. AND 1400*C. IN A REDUCING ATMOSPHERE THAT WILL CAUSE SURFACE OXIDES TO DISAPPERAR AND THE SULFUR CONTENT AT THE TIME SECONDARY RECRYSTALLIZATION IS INITIATED TO BE WITHIN THE RANGE OF FROM 0.00003% TO 0.0006%, BY WEIGHT, FOR A PERIOD OF TIME SUFFICIENT TO ENABLE SUBSTANTIALLY COMPLETE SECONDARY RECRYSTALLIZATION OF THE GRAINS SO THAT AT LEAST 70% OF THE VOLUME OF THE SHEET COMPRISES CUBE GRAINS.