The heating and cooling during the heat treatment equipment will change the shape and size of the metal workpiece after processing, and the reprocessing method will be used to increase the machining allowance. The excessive deformation will cause scrap and cause loss of the invested materials and resources . Deformation of the workpiece will also affect interchangeability and reduce the precision of the operation, resulting in lower efficiency, increased energy consumption and noise.
For this reason, zero distortion in heat treatment is very important, which depends on the accurate production of heat treatment process to ensure. Accurate production is ensured by high-precision and reliable operation of heat treatment equipment, material composition organization and corresponding material thermophysical and process performance deviations are small, so as to reduce the quality difference between batches of the same furnace and make different furnace batch Improved reproducibility of processed product quality.
China's industrial application of induction heating started in the 1950s and the end of the 1950s, with self-made tube-type high-frequency power sources and mechanical intermediate-frequency generators. After the 1960s, thyristor intermediate frequency power supplies were developed. At present, foreign SCR intermediate frequency power supplies in the range of intermediate frequency 150 ～ 10kHz have completely replaced intermediate frequency generator sets and electromagnetic frequency multipliers. Since the reform and opening up, the introduction of modern induction heating technology in industrial developed countries has made great progress in the development of induction heat treatment technology in China.
