Laser surface treatment is a processing technique commonly used in the material industry, especially in the metal material industry. Laser surface treatment can improve the performance of metal products, improve their use efficiency or extend their service life, and sometimes make cheaper metal materials replace more expensive materials. For example, the requirement of surface wear resistance of mechanical parts such as crankshafts and pistons is very high, but there is no such requirement inside. In order to save high-grade alloy materials, usually cheap cast iron is used to make parts, and then laser surface treatment technology is used in its parts. An alloy layer is formed on the surface to achieve the required performance.