Technology Research Of The Continuous High Frequency Induction And Vacuum Cladding

The issue researches how to proceed induction cladding of the coatings and induction cladding of the lap surfaces on a continuous state of motion.Analyze the cladding coatings and the lap surfaces which were gained by different process parameters from the three aspects of microstructure,,microhardness and corrosion resistance. Study the influence rule of the coatings which were gained by different induction cladding process parameters and analyzed how property of the coatings were influenced by the lap surfaces.The current and the platform speed,which are two parameters in induction cladding experiment is in a dynamic relationship. In order to ensure the coatings in molten state,so must reduce the speed of movement of the platform when the current increases.The preheating is needed before the induction heating in order to eliminate the effects of electromagnetic force in the induced magnetic field and reduce the resistivity of the coatings.Through observing the microstructure of the coating see the diffusion layer between the coatings and the substrates. In the process of continuous induction cladding, the current has no influence on the coatings but has impact on the diffusion layer. If the large current is used, eddy current will increase between the coatings and substrates, which result in the serious of stress and the more of defects of diffusion layer. After two induction heating of lap induction cladding coating trials, the diffusion of coating and substrate is more sufficient and mass diffusion layer is better. In the scanning electron micrograph, already can not see signs of lap surface combined well.Through measuring the microhardness of Cladding Coatings and Induction cladding of lap surface coating find microhardness changes along the depth wave in the continuous induction cladding coatings.It is because heating time is short and the elements gathered. The microhardness changes of the lap induction cladding coatings in the same depth presents wave,which is because the first cladding coatings exposing the air is serious than the after coating in burning and oxidation aspects,and diffusion of elements between the two coatings is not sufficient.In the corrosion test of the coatings, the larger current is in induction cladding process, the better corrosion resistance of the coatings is in acid solution, while the corrosion resistance of the coatings in acid solution is decreased because of the presence of the lap induction cladding surface.