Process for cube-on-edge oriented boron-bearing silicon steel including normalizing

• Main Authors: MALAGARI, JR.; FRANK A, SHILLING; JACK W, DATTA; AMITAVA
• Format: Patent
• Language: English
• Published: 21.06.1977
• Subjects: ALLOYS; BASIC ELECTRIC ELEMENTS; CHEMISTRY; ELECTRICITY; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; INDUCTANCES; MAGNETS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES; TRANSFORMERS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

A process for producing electromagnetic silicon steel having a cube-on-edge orientation and a permeability of at least 1870 (G/Oe) at 10 oersteds. The process includes the steps of: preparing a melt of silicon steel containing from 0.02 to 0.06% carbon, from 0.0006 to 0.0080% boron, up to 0.0100% nitrogen, no more than 0.008% aluminum and from 2.5 to 4.0% silicon; casting said steel; hot rolling said steel; cold rolling said steel; normalizing said steel at a temperature of from 1300 DEG to 2000 DEG F in a hydrogen-bearing atmosphere having a dew point of from +20 DEG to +110 DEG F; applying a refractory oxide base coating to said steel; and final texture annealing said steel. The variables of time, temperature and dew point are monitored during normalizing so as to result in a steel having at least 320 parts per million of oxygen, based on the total weight of the steel, within 10 microns of the surfaces of said steel.