Forming method and advantages of thermal spraying filled composite spraying wire

       The manufacturing and wire structure of the filled composite spraying wire are very similar to the flux-cored welding wire used in the welding industry, but in order to be able to send the wire evenly, the composite spraying wire has the uniformity of the structure of the filled powder core and the size of the coated metal tube. Sexual demands are higher. The manufacturing process of the filled powder-core composite wire is as follows: cut a thin steel strip or metal strip into a certain width, extrude it into a U shape by several rollers, and then mix all kinds of powder materials uniformly according to a certain proportion and particle size. Add a small amount of additives such as binder to make powder core, and send it into the U-shaped groove. It is then rolled into shape in several passes. Finally, the diameter is reduced and drawn on the wire drawing machine to the required diameter. It can also be punched into a U-shaped material from a bar, then filled with core material or powder core, and drawn into a material.



The tubular carbide core wire is a tubular powder-core composite spraying wire made of low carbon steel as a sheathed metal tube and Co-WC as a powder core filler. When arc-sprayed carbide tubular composite core wire is used, because the arc temperature is as high as 6000 ℃, both the sheath steel and the powder core carbide are rapidly melted, and the carbide is decomposed at high temperature, and a part of it is solid-dissolved into the iron-based phase to form Alloy, part of which still retains the structure of carbide. The process adjustment range of the arc sprayed tubular carbide powder core composite wire is relatively narrow, and the process parameters, especially the spraying distance, have a relatively large influence on the coating composition and the coating wear resistance. By controlling the proportion, distribution, particle size and shape of the carbide hard phase, different wear resistance properties can be obtained to meet the needs of different wear-resistant coatings. This kind of coating has relatively higher hardness and relatively good wear resistance than pure metal alloy wire arc spray coating, but cannot compare with the excellent wear resistance of explosive spraying and supersonic spraying coatings, but due to the high deposition efficiency, Low cost, suitable for spraying wear-resistant coatings on relatively low-value wear parts.



7Cr13 cored tubular composite wire is a martensitic stainless steel with high carbon content. Due to the high content of C and Cr, it is difficult to produce this high alloy content stainless steel wire by drawing. The high-carbon martensitic stainless steel type flux-cored tubular composite wire is made by using low-carbon steel strip to coat high-carbon and chromium iron core powder through rolling and drawing process. The coating formed by arc spraying of 7Cr13 core-clad tubular composite wire has a typical layered structure. The structure of the coating is mainly high chromium martensite. Due to the oxidation of iron in the high temperature arc, the coating also contains more oxides, and there are certain pores and a small amount of retained austenite. The coating has good bonding strength and relatively high coating hardness, and the coating hardness does not decrease under the condition of elevated temperature, and has relatively good wear resistance and thermal wear resistance. Arc spraying or wire spraying can be used to prepare wear-resistant coatings for normal temperature and heat-resistant wear coatings under elevated temperature conditions.



Self-fluxing flux-cored composite wire is a flux-cored composite wire with self-fluxing alloy element powder added, and a series of composite wire varieties developed on the basis of Fe-B base. In this type of composite wire, the proportion of the core powder is 10%~15%, and the composite wire has good rigidity and is not easy to be twisted. The sprayed coating of this kind of composite wire has an amorphous structure, and the amorphous phase accounts for about 35% to 82% in the coating. The coating has high hardness and good wear resistance under the conditions of sliding wear, abrasive wear and airflow erosion wear. The coating has high bond strength and low porosity. This type of coating is particularly suitable for the protection of components in electrical equipment that require wear and corrosion resistance.