ELECTROMAGNETIC STEEL SHEET WITH ORIENTED STRUCTURE WITH COATING AND PREPARATION METHOD THEREOF Russian patent published in 2016 - IPC C23C22/30 C23C22/33 C23C22/74 C21D8/12 C21D9/46 

FIELD: metallurgy.

SUBSTANCE: invention relates to the production of grain-oriented electrical sheet steel coated. In the method for surface sheet production of grain-oriented electrical steel is applied to the working coating solution comprising primary phosphate salt containing at least one element selected from the group consisting of Mg, Al, Ni, Co, Mn, Zn, Fe, Ca and Ba, colloidal silicon dioxide and at least one compound of chromic acid selected from the group consisting of chromic anhydride, chromate and dichromate salts, followed by calcination, wherein the following condition (i) 800≤T<860, T≥1010-399R, 0.3≤R≤0.5, or (ii) 860≤T≤1000, T≥985-399R, 0.3≤R≤0.5, where T is the steel sheet temperature T (unit: °C) upon calcination, and R is the weight ratio (Cr₂O₃/P₂O₅), Chromic acid compounds (calculated as Cr₂O₃) to a primary phosphate salt (calculated as P₂O₅) in the working coating solution.

EFFECT: invention provides an improvement in the tensile stress produced by coating on a sheet made of grain-oriented electrical steel and reducing losses in the iron sheet.

2 cl, 1 dwg, 1 tbl