The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 29, 1977
Filed:
Sep. 16, 1975
Mario Barisoni, Albano Laziale, IT;
Massimo Barteri, Rome, IT;
Roberto Ricci Bitti, Lanuvio, IT;
Pietro Brozzo, Albano Laziale, IT;
Edmondo Marianeschi, Terni, IT;
Centro Sperimentale, Metallurgico S.p.A., Rome, IT;
Terni Societa per l'Industria e l'Elettricita S.p.A., Rome, IT;
Abstract
A process for the production of oriented-grain high magnetic permeability steel sheet including the steps of continuously casting a steel slab haing a weight % composition within the range of 2.5-3.5 Si, 0.01-0.04 S, less than 0.07 C, less than 0.15 Mn, and an acid-soluble aluminum in an amount between 0.01 and 0.05, at a feed rate ranging from 700 to 1000 kg/minute, into an ingot mold of a length over 1200 mm and cooling it in said ingot mold with a quantity of water ranging from 2.8 to 4 m.sup.3 per ton of steel; heating the slab so obtained to 1300.degree.-1400.degree. C and immediately thereafter hot-rolling it to a thickness in the range between 2 and 3.1 mm, annealing the strip so obtained at a temperature in the range between 1050.degree. and 1150.degree. C, keeping it at this temperature for a duration between 5 and 30 seconds; cooling it at any desired cooling rate to 750.degree.-850.degree. C at a temperature at which austenite is still present in it; keeping the strip at this temperature for a duration ranging from 30 to 200 seconds; and finally quenching it from the initial quenching temperature of 400.degree. C at a cooling rate of between 10.degree. C/second and 100.degree. C/second; cold-rolling the strip so obtained with a reduction rate ranging from 80 to 90% and subjecting it finally to the decarburization and recrystallization annealing operations as well as to other final anneals.