Reducing cost and increasing efficiency is the ultimate goal pursued by enterprises. Looking at many major technological breakthroughs in the history of steel industry technology, such as converter steelmaking, continuous casting, continuous rolling, etc., their primary motivation is to reduce costs. Metallurgical technology is quite mature today, and the use of remanufacturing technology can extend the service life of the core components of metallurgical production line. It's not only can improve the performance of new products, but also repair waste products and extend product life. At the meantime,it effectively reduces equipment maintenance and downtime.
The basic principle of laser quenching
Laser quenching technology is the use of focused laser beam as a heat source, irradiating on the surface of the workpiece to be treated, so that the temperature of the hardened parts rises sharply in an instant, which forms austenite and then rapidly cools to obtain martensite or other fine-grain structure of the hardened layer .
Technical characteristics of laser quenching
1. High power density, fast heating speed, small deformation of parts
The heat treatment process can control the deformation, and the processed workpiece does not need grinding, which can be used as the last process of parts finishing.
2. Can be used for complex shape parts
Such as blind holes, inner holes, small slots, thin-walled parts, etc. It can be done or done in part, or it can be done differently in different parts of the same part as needed. It can overcome the high frequency quenching due to the limitation of the inductor. It's difficult to quench the surface of the parts with complex shapes, and the heating area is difficult to control and are easy to crack during quenching. In the process of chemical heat treatment such as carburizing and quenching, the processing of large parts does not need to be limited by the size of the furnace.
3. Universality
The deep focus of the laser has no strict restrictions on the size, dimension and surface of the part during quenching. However, the existing medium and high frequency quenching must produce sensors suitable for various parts.
4. No restrictions
For some stainless steel parts with higher quenching temperature, the quenching temperature is very close to the melting point temperature. When the sensor is used for local surface quenching of the product, it is easy to burn corners or irregular parts, resulting in the scrap of parts, however, laser surface quenching is not subject to this limitation.
5. No need to cool
Laser quenching is a clean, efficient and environmentally friendly quenching process, with fast cooling speed and no need for cooling media such as water or oil.
6. Meet hardening requirements
The surface hardened layer has fine structure, high hardness and good wear resistance, and can meet the product requirements of shallow surface hardened layer depth (generally 0.3 ~ 2.0mm).
Application example of laser quenching technology in steel industry
1. Laser alloying of roll
Roll is the main working part and tool to produce continuous plastic deformation of metal in a steel rolling mill. Long-term harsh working conditions will lead to surface peeling, cracks and even fractures. Alloying the roll with laser can effectively extend the service life of the roll. Through the laser alloying treatment of rod roller, it has no deformation, high-temperature resistance, or corrosion resistance, and the steel passing ability is significantly improved.
2.Roll-bottom laser quenching
As the transmission medium of the high-temperature slab, the bottom roll of the furnace works in a high-temperature environment full of corrosive gas for a long time. The surface of the roller ring in direct contact with the high-temperature slab is prone to steel sticking, nodulation, oxidation, corrosion, wear, high-temperature creep and other phenomena, especially various quality defects such as pits, scratches and heavy skin on the bottom surface of the slab caused by steel sticking and nodulation. In silicon steel, cold rolled raw materials and other soft steel performance is particularly outstanding. A layer of new material with high temperature resistance, oxidation resistance and abrasion resistance is laser quenched on the surface of the roller ring. During the service life of the furnace bottom roll, the surface nodules or the oxide skin is loose and spalling, which may affect the rolling quality of steel plate and billet, and can effectively improve the economic benefit of the production line. Laser quenching technology can strengthen the surface of various guides, large gears, journals, cylinder walls, die, shock absorbers, friction wheels, roller, and roller parts. Applicable materials are medium and high-carbon steel and cast iron.
Xi'an Guosheng Laser Technology Co., Ltd. is a high-tech enterprise specializing in R&D, manufacturing and sales of automatic laser cladding machine, high-speed laser cladding machine, laser quenching machine, laser welding machine and laser 3D printing equipment. Our products are cost-effective and sold domestically and abroad. If you're interested in our products, please contact us at bob@gshenglaser.com.