A kind of coating of welding rod and the method for preparing it into welding rod

Abstract

The invention discloses a welding electrode coating. The welding electrode coating is composed of, by weight, 5-7 parts of diamond, 18-22 parts of reduced ilmenite, 4-6 parts of kaolin, 13-16 parts of light calcium powder, 22-25 parts of iron red, 2-4 parts of talcum powder, 10-14 parts of aluminum powder, 1-3 parts of sodium carbonate, 4-6 parts of wood meal, 4-7 parts of titanium dioxide and 3-6 parts of ferromanganese. A binder of the welding electrode coating is sodium silicate or potassium silicate water glass, and 30-36 g of water glass is added into each100 g of the welding electrode coating. Raw materials are low in price, so that the coating prepared is low in cost. When the welding electrode prepared by the welding electrode coating is used for welding, welding defects like air holes, slag inclusion and cracks do not appear on the welding surface, and welding seam forming is smooth; an electric arc is stable in burning, splashing particles are small, slag removing is easy after welding, and the coating is uniform in melting and free of caking and shedding; a conventional knife and conventional cutting parameters are adopted to machine a welding joint, knife beating in the machining process is avoided, no knife relieving trace is formed on a cut surface, and machining performance is good.

Description

technical field [0001] The invention belongs to the field of welding materials, and in particular relates to a welding rod coating and a method for preparing it into a welding rod. Background technique [0002] As an important engineering material, cast iron is widely used in the machinery manufacturing industry due to its low cost, good casting performance, and excellent shock absorption performance. Among them, gray cast iron is the most widely used cast iron, and its output accounts for more than 80% of the total output of cast iron. Among the blanks of mechanical equipment, gray iron parts account for about 50%. According to statistics, in the production of castings, the scrap rate is as high as 20% due to various reasons, and the loss is serious. [0003] At present, the best way to reduce losses is to repair the waste products through repair welding. Due to the extremely poor weldability of gray cast iron, there are mainly the following problems in welding repair: Fi...

AI Technical Summary

Problems solved by technology

Due to the extremely poor weldability of gray cast iron, there are mainly the following problems in welding repair: First, the welded joint is difficult to machine. Easy to produce cementite (Fe 3 C) White structure is formed, and the hardness of white cast iron structure is as high as HB800, which makes it difficult to machine gray iron parts after welding repair

The second is that the welded joints are prone to cracks. Gray cast iron itself has low strength and poor plasticity, and the uneven heating during the welding process causes cracks to easily occur in the weld seam and heat-affected zone. Much larger, making the stress more severe and increasing the tendency to crack

[0004] At present, there are many types of welding electrodes specially used for gray cast iron welding repair, but there are very few welding electrodes that can meet the weldability requirements of gray cast iron and reduce welding costs