HIGH-TEMPERATURE OXIDATION-PROOF COATING FOR ELECTRODE

摘要

PURPOSE:To obtain titled coating capable of giving calcined coating layer of high adhesiveness and airtight performance, by formulating specific ingredients such as silicone carbide in specific ratio. CONSTITUTION:The objective coating can be obtained by formulating the following ingredients: (A) 40-75wt% of silicon carbide, (B) 15-40wt% of heat-radiating agent (also serving as binder) made up of (i) 3-20pts.wt. of silicon nitride (ii) 5-20pts.wt. of phosphate, (iii) 2-10pts.wt. of chromium oxide, (iv) 2-10pts.wt. of tantalum carbide and (v) 5-20pts.wt. of aluminum powder, (C) 10-35wt% of additive made up of (i) 1-10pts.wt. of aluminum oxide, (ii) 3-15pts.wt. of glass powder, (iii) 3-15pts.wt. of zirconium oxide, (iv) 1-10pts.wt. of silicon dioxide, (v) 1-10pts.wt. of magnesium oxide and (vi) 1-10pts.wt. of iron oxide, (D) 5- 20wt% of methallic powder made up of each 0-40pts.wt, of copper, nickel, stainless steel, iron and tin, (E) 2-50wt% of sintering agent mixture made up of (i) 10-30pts.wt. of silver carbide and (ii) 30-50pts.wt. of copper sulfate and/or (iii) 30-50pts.wt. of iron sulfate, and (F) 3-7wt% of melting point depressant made up of (i) 30-60pts.wt. of iron fluoride and (ii) 70-40pts.wt. of copper fluoride.