Laser heat treatment process and equipment

Since the advent of the laser in the 1960s, laser technology has been used as an eye-catching high-tech, and has gained important applications in almost every industry. In recent years, laser surface treatment technology has not only developed rapidly in research and development, but also made great progress in industrial applications. Laser surface treatment can improve the surface hardness, wear resistance, corrosion resistance, strength and high temperature performance of the parts. At the same time, the core of the parts can still maintain good toughness and the mechanical properties of the parts are significantly improved. Among them, laser phase transformation hardening is one of the most research and application methods of various laser surface treatment technologies, and has been applied and developed in many fields such as automobiles.

Laser heat treatment and surface modification are the key technologies for today's effective use of materials and design performance. These technologies can improve the performance of automotive parts and extend the service life in the automotive industry.

In the past 10 years, the rapid development of the automotive industry has promoted the development of laser heat treatment. Laser heat treatment is now widely used in the automotive industry and is used in many automotive key components such as engine blocks, cylinder liners, crankshafts, camshafts, valve seats, rocker arms, aluminum piston ring grooves, housings, and alloy steel engines. Valves, steel gears, steel piston rings, malleable cast iron steering gear housings and synchronizer shift rings. Beijing Shouqi Company installed a laser heat treatment production line for automobile engine cylinder liners, and FAW installed a laser heat treatment production line. China adopts high-power CO2 laser to strengthen the cylinder bore of the automobile engine, which can extend the overhaul mileage of the engine to more than 150,000 km. One cylinder is equal to three cylinders without laser treatment. Laser quenching of automobile toothed plates (low carbon steel) can achieve higher hardness and less deformation than conventional carburizing and quenching. The automobile mold is deformed by laser quenching and can be quenched several times. Chery Automobile Company solved the problem of pulling the mold of automobile cover parts by laser heat treatment technology, which not only improved work efficiency and production quality, but also greatly extended the service life of the mold.

With the development of China's 10,000-watt high-power CO2 multimode laser, various forms of surface treatment can be realized with laser. At present, the company represented by Wuhan Dazu Jinshikai Laser System Co., Ltd. has produced a series of laser heat treatment equipment, such as HANSGS-W6000 low-order mode cross-flow CO2 laser for automotive industry (see Figure 4) and HANSGS- RM large mold laser heat treatment equipment (see Figure 5).

Figure 4 HANSGS-W6000 low-order mode cross-flow CO2 laser

Figure 5 HANSGS-RM large mold laser heat treatment equipment

Laser heat treatment is developing in the direction of high-power lasers, multi-degree-of-freedom processing equipment and computer, and real-time control systems for laser heat treatment processes in different situations.