The difference between intermediate frequency quenching and high frequency quenching, help you distinguish between the two-Kehua

Intermediate frequency quenching and high frequency quenching are two very common types in modern quenching process. Many people can't tell the difference between the two. In order to help you distinguish the two, we will share the difference between intermediate frequency quenching and high-frequency quenching for you below. The difference between intermediate frequency quenching and high frequency quenching Austenitizing, and then rapidly cooling below Ms (or isothermal near Ms) at a cooling rate greater than the critical cooling rate for martensitic (or bainite) transformation. The solution treatment of aluminum alloy, copper alloy, titanium alloy, tempered glass and other materials or the heat treatment process with rapid cooling process is also called quenching. 2. What is the difference between intermediate frequency quenching and high-frequency quenching? The working principle of high-frequency quenching and intermediate-frequency quenching is the same as that of induction heating: that is, the workpiece is placed in the inductor, and the inductor is generally input with intermediate frequency or high-frequency alternating current (1000- 300000Hz or higher) hollow copper tube. The alternating magnetic field generates an induced current of the same frequency in the workpiece. The distribution of this induced current in the workpiece is uneven, it is strong on the surface, but very weak in the interior, and it is close to 0 in the center. This skin effect is used. , the surface of the workpiece can be heated rapidly, the surface temperature rises to 800-1000 ℃ in a few seconds, and the temperature of the core part is very small. Kehua believes that the two main differences are as follows. 1. The current frequency of high-frequency quenching is 100-500 kHz; the hardened layer is shallow (1.5-2mm); the hardness is high; the workpiece is not easy to oxidize; the deformation is small; the quenching quality is good; Such as generally smaller gears and shafts (the materials used are 45# steel, 40Cr); 2. The frequency of the intermediate frequency quenching current is 500 ~ 10000 Hz; the hardened layer is deep (3 ~ 5mm); suitable for bearing distortion and pressure loads parts, such as crankshafts, large gears, grinder spindles, etc. (the materials used are 45# steel, 40Cr, 9Mn2V and ductile ink; in short, the biggest difference between high-frequency quenching and intermediate-frequency quenching is the difference in heating thickness, and high-frequency quenching can Short-term surface hardening, the crystal structure is very fine, the structural deformation is small, and the intermediate frequency surface stress is smaller than the high frequency. The difference between intermediate frequency quenching and high frequency quenching 3. The application of quenching process The quenching process is widely used in the modern machinery manufacturing industry Application. Important parts in machinery, especially steel parts used in automobiles, airplanes, and rockets are almost all quenched. In order to meet the technical requirements of various parts, various quenching processes have been developed. For example, according to the acceptance The treated parts include overall, local quenching and surface quenching; according to whether the phase transformation is complete during heating, there are complete quenching and incomplete quenching (for hypoeutectoid steel, this method is also called subcritical quenching); according to the phase transformation during cooling The content includes graded quenching, isothermal quenching and under-speed quenching, etc. The process includes three stages of heating, heat preservation, and cooling. The following takes steel quenching as an example to introduce the principles of selection of process parameters in the above three stages. The difference between quenching is mainly reflected in hardness, efficiency, etc. After reading the above content, you will be able to distinguish clearly. In short, you can choose which process according to your own needs.