Process for preparing unidirectional silicon steel sheet having high magnetic flux density
US5049205A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 27, 1990 |
| Grant date | Sep 17, 1991 |
| Priority date | — |
| Expiry date | Sep 27, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC21D8/1283
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention relates to a process for preparing a unidirectional silicon steel sheet having a high magnetic flux density which comprises heating a silicon steel slab comprising by weight 0.025 to 0.075% of carbon, 2.5 to 4.5% of silicon, 0.015% or less of sulfur, 0.010 to 0.050% of acid-soluble aluminum, 0.0010 to 0.012% of nitrogen, 0.050 to 0.45% of manganese and 0.01 to 0.10% of tin and optionally 0.0005 to 0.0080% of boron with the balance being iron and unavoidable impurities, at 1200.degree. C. or below; hot-rolling the slab; subjecting the slab to rolling once or two or more times wherein intermediate annealing is provided, thereby attaining a percentage final rolling of 80% or more; subjecting the resultant steel sheet to decarburizing annealing in a wet hydrogen atmosphere; coating the steel sheet with an annealing separator; conducting finishing annealing for secondary recrystallization and purification of the steel; and subjecting the steel sheet to a nitriding treatment between after the ignition for decarburizing annealing and before the initiation of the secondary recrystallization in the finishing annealing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.