By analyzing the material characteristics, usage conditions, service conditions, and other factors of quenched parts, the technical conditions and product quality requirements are clarified, and then the laser quenching hardening model is selected and the laser quenching process parameters are determined. At the same time, the operability, production efficiency, and economic benefits of the process should also be considered. The laser beam mode is divided into multimode beam, low-order mode beam, and fundamental mode beam, which are generally used for laser heat treatment.

The metal surface of laser heat treatment is generally processed by mechanical processing, with small surface roughness and high reflectivity to laser. Before laser heat treatment, the quenched surface should be pre treated to improve its absorbance. After oil removal, rust removal, cleaning, and drying of the treated surface, a light absorbing coating (blackening) is pre installed on the surface. The methods include phosphating, spraying (brushing) paint, improving surface roughness, oxidation, coating, etc; The coating should be thin, uniform in thickness, with a high laser absorption rate (over 90%), good thermal conductivity, good adhesion to metal, and not decompose or evaporate at a certain temperature. It is easy to clean and remove after quenching or can be used without removal.