ELECTRIC INSULATING COATING FOR ELECTRO-TECHNICAL ANISOTROPIC STEEL WITH HIGH TECHNICAL AND COMMERCIAL QUALITY Russian patent published in 2020 - IPC C23C22/20 C23C22/24 C23C22/33 

FIELD: metallurgy.

SUBSTANCE: invention relates to production of electrical anisotropic steel used for production of power and distribution magnetic conductors of transformers. Disclosed is composition of electrically insulating coating for anisotropic electrical steel, containing aluminum and magnesium phosphates, silicic acid sol, a modifying additive in form of zirconium silicate and a modifying additive based on chromium compounds (CrVI+CrIII), with the following ratio of components, wt%: phosphates A1 and Mg 20–40, silicic acid sol (with concentration of SiO₂ 10–30 %) 20–40, modifying additive zirconium silicate (ZrSiO₄) 1–12, modifying additive of chromium compounds (CrVI+CrIII) 0.5–5, water up to 100. As a modifying additive based on chromium compounds (CrVI+CrIII), it is recommended to use a mixture of CrIII+CrVI compounds, having the following ratio, wt%: CrVI compounds 20–80, compounds CrIII 20–80, wherein the sum of CrVI+CrIII compounds in the specified range values – 100 %.

EFFECT: proposed composition of electric insulating coating provides high technical characteristics – adhesion to metal, dielectric properties of coating (coefficient of resistance), corrosion and moisture resistance, as well as commercial appearance.

1 cl, 2 tbl