METHOD OF BORATING OF STEEL SURFACE FOR ENAMELING Russian patent published in 1999 - IPC

FIELD: thermochemical treatment of steel. SUBSTANCE: method includes heating of steel surface to 390-410 C and direct borating without use of electric current in electrolyte with temperature of 18-25 C containing, wt.%: borax, 3.0-7.0; potassium boron hydride, 0.4-0.6; water, the balance; washing with cold water and drying at temperature of 70-100 C. Electrolyte solution may additionally contain potassium carbonate in the amount up to 1 wt. %. The method allows production of steel surface of boride layer with absolute continuity and subsequent enamel coating which in its chemical stability, luster, adhesion strength and heat resistance meets the requirements of respective standards. EFFECT: higher efficiency. 2 cl