Back to results
US 3,971,678 AGranted
Method of making cold-rolled sheet for electrical purposes
AssigneeStahlwerke Peine-Salzgitter AG
InventorConstantin Vlad
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeStahlwerke Peine-Salzgitter AG
InventorConstantin Vlad
Estimating the term…
Alloy steel sheeting for electrical purposes such as the cores of transformers, is made with isotropic magnetic properties by a method in which steel containing, by weight, up to 0.1% carbon, from 0.15 to 0.35% manganese, from 0.3 to 2.4% aluminium up to 0.25% copper, up to 0.5% sulphur, up to 0.2% phosphorus, up to 2.0% silicon and the balance iron except for impurities is hot rolled at a temperature of from 820.degree. to 1080.degree.C to cause at least 5% of it to have a crystal orientation {100} <hkl>. After this the sheet is cold-rolled with a reduction in cross-section of from 50% to 85% and then it is recrystallization-annealed at a temperature of from 820.degree. to 1200.degree.C. Preferably the cold-rolling is carried out in two stages and the sheet is annealed for from 10 to 30 minutes at a temperature of from 550.degree. to 950.degree.C between the two stages.
A method of making cold-rolled sheet for electrical purposes, said sheet having isotropic magnetic properties, said method comprising the steps of hot rolling at a temperature of from 820.degree. to 1080.degree.C a steel consisting essentially of up to 0.1% carbon, from 0.15% to 0.35% manganese, from 0.3% to 2.4% aluminium, up to 0.25% copper, up to 0.05% sulphur, up to 0.2% phosphorus, up to 2.0% silicon and the balance iron except for impurities, to bring at least 5% of the grains into a {100} <hkl>
Dependencies are inferred from the claim text.