1. Hardened parts are not deformed. The thermal cycle of laser hardening is fast, medium-sized carbon steel large shafts 2. Hardly damage the surface roughness, using anti-oxidation protection thin-coated die steel, various die steels 3. Laser quenching without cracking, precise and quantitative numerical control quenching cold work die steel, die steel, cutting tools 4. 4. CNC quenching medium-carbon alloy steel shock absorber with accurate positioning for local, groove and groove quenching 5. Laser quenching is clean, efficient and does not require cooling media such as water or oil. Cast iron engine cylinders. Laser quenching technology uses a focused laser beam to quickly heat the surface of steel materials to undergo phase transformation and form a hardened martensite layer. Laser quenching of die steel has high power density and fast cooling speed. It does not require cooling media such as water or oil. It is a clean and fast quenching process. Compared with induction hardening, flame hardening, 100121dzmgz carburizing and hardening process, laser hardening hardened layer is uniform, high hardness (generally 1-3HRC higher than induction hardening), workpiece deformation is small, heating layer depth and heating track are easy to control, and easy to realize Automation does not need to design corresponding induction coils according to different part sizes like induction hardening, and the processing of large parts does not need to be restricted by the furnace size during chemical heat treatment such as carburizing and quenching. Therefore, induction hardening and induction hardening are being gradually replaced in many industrial fields. Traditional processes such as chemical heat treatment. It is especially important that the deformation of the workpiece before and after laser quenching is almost negligible, so it is especially suitable for the surface treatment of parts with high precision requirements. The depth of the laser hardened layer depends on the composition, size and shape of the part, and the laser process parameters, generally in the range of 0.3~2.0mm. The tooth surface of large gears and the journals of large shaft parts are quenched, and the surface roughness is basically unchanged. It can meet the needs of actual working conditions without subsequent machining. Laser melting and quenching technology is a process in which the surface of the substrate is heated to above the melting temperature by a laser beam, and the surface of the molten layer is rapidly cooled and solidified and crystallized due to heat conduction and cooling inside the substrate. The obtained melting and quenching structure is very dense, and the structure along the depth direction is in order of melting-solidification layer, phase change hardening layer, heat-affected zone and base material. The laser fused layer has a deeper hardening depth, higher hardness, and better wear resistance than the laser hardened layer. The disadvantage of this technology is that the surface roughness of the workpiece is damaged to a certain extent, and generally requires subsequent machining to recover. In order to reduce the surface roughness of the parts after laser fusion treatment and reduce the amount of subsequent processing, Huazhong University has formulated a special laser fusion quenching coating, which can greatly reduce the surface roughness of the fusion layer. The surface roughness of rolls, guides and other workpieces of various metallurgical materials that are currently subjected to laser fusion treatment is close to the level of laser quenching. Laser quenching has been successfully applied to the surface strengthening of vulnerable parts in the metallurgical industry, machinery industry, and petrochemical industry, especially in improving the service life of rolls, guides, gears, shears and other vulnerable parts. The effect is significant. Great and social benefits have been achieved. In recent years, it has also been widely used in the surface strengthening of mold steel, gears and other parts.