The wear-resistant material plasma arc surfacing technology adopts the plasma arc surfacing method, which utilizes the high temperature of the plasma arc and the high current density. The high-hardness particles are evenly brazed into the weld overlay metal, while the hard particles do not melt or rarely melt. Form a composite weld overlay. This composite weld overlay is composed of two or more macroscopically Different kinds of different materials. One is carbide hard particles which are mainly wear-resistant in the surfacing layer, generally cast tungsten carbide, chromium carbide, boron carbide, sintered tungsten carbide, etc. In principle, various Carbides, borides and even higher hardness diamonds can be used as a composite of the surfacing layer. Domestic and foreign industrial composites are used for plasma arc surfacing. The hard particles that are welded more are cast tungsten carbide, which is composed of eutectic. Composition, hardness is 250~300. Another component of the surfacing layer is the base metal which acts as a "knot", also known as the carcass metal, which is the matrix in the surfacing layer. It is generally considered to be hard. The combination of the granular particles and the carcass metal is brazed, and the combination of the surfacing layer and the parent metal is metallurgical bonding.
The quality of the composite surfacing layer obtained by plasma arc surfacing technology is stable and reliable. The latest development of composite plasma arc surfacing technology can make the surfacing layer reach defects such as no porosity, crack and carbide burning, melting and so on. Carbide particles are in The distribution in the surfacing layer is uniform. The wear-resistant material surfacing layer has high wear resistance. Under the condition of severe wear, the wear resistance of the composite surfacing layer is particularly outstanding, which can be compared with the common iron, cobalt and nickel-based alloys. The surface protective layer improves the wear life by several times or even ten times. It has a high bonding strength. Since the surfacing layer is metallurgically bonded to the surface of the workpiece to be protected, it can meet high strength requirements. Compared with the wear-resistant protective layer, the bonding strength of the surfacing layer is 3-8 times of the bonding strength of the thermal spraying layer. The composite surfacing layer can meet certain impact resistance requirements. For example, the limestone crusher hammer of the cement production equipment is worn due to wear. The impact force in the process is relatively large. Generally, the high manganese steel material is used, and the service life is low. After the surface is welded with the high carbon high chromium alloy, the weld overlay layer is easily broken and peeled. Solder layer may prevent this from happening, and significantly improved wear resistance may be realized Higher automated production, reduce labor intensity and improve the working conditions improve labor productivity.