REFORMING METHOD OF SI, AL OR FERROALLOY POWDER THEREOF FOR COATED ELECTRODE

摘要

PURPOSE:To obtain a coated electrode having high quality by coating dimethyl silicone oil on Si, Al or ferroalloy thereof which is a raw material then mixing the other raw material for the coating material therewith thereby suppressing reaction with water glass. CONSTITUTION:Dimethyl silicone oil diluted by a solvent is added to 100pts.wt. Si, Al or ferroalloy powder thereof to be used as a raw material for a coated electrode so as to be incorporated at 0.5-6pts. and the mixture is heated and dried to form coating on the metallic powder. The other raw material for the coating agent is then mixed therewith. The film having high alkali resistance and water repellency is applied on the surface of the metallic powder by the above-mentioned method. The reaction between the metallic powder and water glass is thus suppressed and generation of gas is considerably decreased, by which the welding rod having high quality free from swelling and cracking of the coating layer is formed.