Laser surface treatment is a common processing technology in material industry, especially in metal material industry. Laser surface treatment can improve the performance of metal products, improve their use efficiency or prolong their service life. Sometimes cheaper metal materials can replace more valuable materials. For example, the surface wear resistance of mechanical parts such as crankshaft and piston is very high, but there is no such requirement inside. In order to save high-grade alloy materials, cheap cast iron is usually used to make parts, and then an alloy layer is formed on the surface by laser surface treatment process, so as to achieve the required performance.
Laser is the heat source with the highest energy density at present, and it has good directivity, monochromaticity and coherence. Using these characteristics to optimize the surface treatment of metal or parts (including laser transformation hardening, laser “glazing”, laser alloying and laser coating, etc.) can change the surface microstructure of metal or parts, so as to improve their mechanical and physical and chemical properties, It is mainly to improve the wear resistance, corrosion resistance and fatigue resistance of parts.