ANNEALING SEPARATOR FOR GRAIN-ORIENTED ELECTRICAL SHEET STEEL Russian patent published in 2015 - IPC C23C22/00 C21D1/70 C21D8/12 

FIELD: metallurgy.

SUBSTANCE: annealing separator contains 0.01-0.05 wt % of Cl, 0.05-0.15 wt % of B, 0.1-2 wt % of CaO and 0.03-1.0 wt % of P₂O₃, and primarily consists of magnesium oxide having degree of activity of citric acid of 30-120 s as measured at 40% CAA; specific surface area of 8-50 m²/g as measured by a BET method; degree of hydration of 0.5-5.2 wt % as measured in terms of ignition loss; and content of particles, each having a particle diameter of 45 mcm or more, of 0.1 wt % or less, the annealing separator further containing a water-insoluble compound having a particle diameter of 45-150 mcm in an amount of 0.05-20 wt %, inclusively, which is an oxide different from magnesium oxide.

EFFECT: providing an annealing separator for gain-oriented electrical sheet steel which does not inhibit the flowability of an atmospheric gas during final annealing in the form of a conical roll and can prevent surface roughness.

2 cl, 2 dwg, 2 tbl, 2 ex