MAGNESIUM OXIDE FOR ANNEALING SEPARATORS AND ANISOTROPIC ELECTROTECHNICAL SHEET STEEL Russian patent published in 2020 - IPC C23C22/00 C01F5/08 C21D8/12 C21D9/16 H01F1/147 

FIELD: chemistry.

SUBSTANCE: invention relates to magnesium oxide for annealing separator, suitable for production of anisotropic electrical steel plate with excellent magnetic and insulating properties. Proposed magnesium oxide for an annealing separator has a specific surface area of 12.0 × 10³ to 25.0 × 10³ m²/kg Blaine specific surface area of from 2.0 × 10³ to 7.0 × 10³ m²/kg. Magnesium oxide contains from 0.04 to 0.15 wt. % of boron and has content of chlorine of not more than 0.05 wt. %.

EFFECT: disclosed magnesium oxide for an annealing separator provides formation of a forsterite film, having excellent characteristics with respect to the degree of formation of the forsterite film, the appearance of the film, film adhesion and removal of unreacted magnesium oxide from the acid on the surface of the sheet steel.

4 cl, 3 tbl, 11 ex