Research On The Warm Compaction System With Induction Heating

The application of induction heating method in the warm compaction system of powder metallurgy (PM) was introduced in this thesis. And under the condition of a preliminarily designed induction heating system used in the warm compaction, the warm compaction technology for iron-based materials was studied.At first, on the basis of the analysis of several common warm compaction heating methods, the induction heating method was suggested to be suitable for the warm compaction system. According to the theory of induction heating and heat conduction, the parameters of heater coil in the die, powder-delivering device, upper hopper and so on was calculated and checked in detail. Through the analysis and comparison of the real effects of induction heating and resistance heating it was proved that the heating rate, heating uniformity and temperature control precise of the induction heating method is better, than those of the resistance heating method, which is beneficial for the warm compaction technology. According to the law of heat conduction and the equation of heat transfer, a simulation model was built for the induction heating according to the law of heat conduction and the equation of heat transfer, and simulated the induction heating process was simulated of induction heating by using the finite element analysis software ANSYS, obtained the temperature field data and distribution law of the heated die heating were obtained by the simulation, while the simulation results showed that the temperature field around in the radial direction of the die and is in good concordance with the actual test results. were in quite accord, the temperature-time curves temperature curves varying with time are also in large the same tendency, using the method of induction heating may control the temperature difference of the inner and outer surface of the die can be controlled in the range of 0 to 3 degrees celsius by using the of the induction heating method, and the temperature distribution is very uniform, which are the advantages of the induction heating. In the last section of the thesis, the warm compaction technology with the induction heating system was used to form a real product and the planetary gear, some parameters affected on the product density, properties, corresponding stripping pressure, spring back effect, etc. Of the iron-based materials were analyzed and studied. The optimal parameters of the warm compaction process by induction heating for the iron-based materials were obtained, i.e, the compacting pressure is 750MPa, the temperatures of the powder and the die are 85℃and 135℃respectively. Under this condition, the highest density of green compact is 7.323 g/cm~3, much higher than that of common PM process. It was proved that of using the induction heating method is effective for the warm compaction system.