Introduction of surface quenching of Shenzhen high frequency quenching
If you are a worker in the industrial industry, then you must know high frequency quenching, which is mainly used for surface quenching of industrial metal parts. Using induction heating and then surface quenching, the following is the surface quenching introduction of Shenzhen high-frequency quenching shared by Kehua. Shenzhen high-frequency quenching is used for workpieces subjected to alternating loads such as torsion and bending. The surface layer is required to withstand higher stress or wear resistance than the core, and the surface of the workpiece needs to be strengthened. Suitable for carbon content Weu003d0.40~ 0.50% steel. Process method 1. Combination of rapid heating and immediate quenching and cooling. 2. Through rapid heating, the surface of the steel to be processed reaches the quenching temperature, and the heat is not transmitted to the center, which is rapidly cooled, only the surface layer is quenched into martensite, and the center is still annealed with the original unquenched plasticity and good toughness ( Or normalizing and tempering) organization. Main methods Induction heating surface quenching (high frequency, medium frequency, power frequency), flame heating surface quenching, electrical contact heating surface quenching, electrolyte heating surface quenching, laser heating surface quenching, electron beam heating surface quenching. The basic principle is that the workpiece is placed in an inductor wound with a hollow copper tube, and after the intermediate frequency or high frequency alternating current is applied, an induced current of the same frequency is formed on the surface of the workpiece, and the surface or part of the part is rapidly heated (that is, within a few seconds). It can be heated up to 800~1000℃, and the heart is still close to room temperature), and then spray (immersion) water cooling (or spray immersion oil cooling) immediately after a few seconds to complete the immersion work, so that the surface or part of the workpiece can meet the corresponding hardness requirements. Frequency selection 1. The relationship between the depth δ (mm) of the induced current flowing into the surface layer of the workpiece at room temperature and the current frequency f (HZ) is 2. The frequency increases, the current penetration depth decreases, and the hardening layer decreases. The commonly used current frequencies are: 1. High frequency heating: 100~500KHZ, commonly used 200~300KHZ, it is a tube type high frequency heating, the depth of the hardened layer is 0.5~2.5mm, suitable for small and medium-sized parts. 2. Intermediate frequency heating: The current frequency is 500~10000HZ, commonly used 2500~8000HZ, and the power supply equipment is a mechanical intermediate frequency heating device or a thyristor intermediate frequency generator. The depth of the hardened layer is 2~10 mm. Suitable for larger diameter shafts, medium and large gears, etc. 3. Power frequency heating: The current frequency is 50HZ. Using mechanical power frequency heating power supply equipment, the hardened layer depth can reach 10~20mm, which is suitable for surface quenching of large diameter workpieces. Comparison Compared with ordinary heating and quenching, it has: 1. The heating speed is extremely fast, which can expand the transformation temperature range of A body and shorten the transformation time. 2. After quenching, the surface layer of the workpiece can get extremely fine cryptocrystalline martensite, and the hardness is slightly higher (2~3HRC). Lower brittleness and higher fatigue strength. 3. The workpieces treated by this process are not easy to be oxidized and decarburized, and even some workpieces can be directly assembled and used after treatment. 4. The hardened layer is deep, easy to control and operate, easy to realize mechanization and automation. 5. Flame surface heating and quenching Shenzhen high-frequency quenching Through Kehua's introduction to Shenzhen's high-frequency quenching surface quenching, I believe that my dear friends have a certain understanding of this. If you like our articles, please pay more attention to us. There are more and better articles to push to friends.