| 310S stainless steel is used as inner cover material for the annular annealing furnace and is easy subjected to high temperature oxidation failure because of its long-term use in high temperature environment. The aim of this paper is mainly to research the method of improving the oxidation resistance of 310S stainless steel materials and study diffusion mechanism between the aluminum coating and 310S stainless steel substrate under the high temperature.In the process of metal oxidation, if a stable, dense oxide film formed on the metal surface, the film will isolate the oxygen from the substrate and avoid the further oxidation of the metal which makes the metal has a certain antioxidant properties. Aluminum is the first choice to form a protective oxide film. This paper adopted arc spraying method and pack aluminizing method to produce aluminum coating on 310S stainless steel. Aluminum coating were subjected to different diffusion treatments to obtain different forms of diffusive aluminum coating to improve the high temperature oxidation resistance of the substrate. In this paper, optical microscope (OM), scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and X ray diffraction (XRD) methods were used to analyze the change of metallurgical structure of the coating layer, the formation of aluminide diffusion layer and the diffusion law of aluminum element under the heating treatment process. Matano method (Boltzmann-Matano method) was used to calculate the diffusion coefficient of aluminum atoms in the matrix of 310S stainless steel. Additionally, this paper simulated the diffusion process with the varied diffusion coefficient from experiments, and compared the results with the experimental results to verify its accuracy. Finally, high temperature oxidation experiments and oxidation kinetics analyses were carried out to obtain the best surface treatment technology which can improve the high temperature oxidation resistance of 310S stainless steel. |
PDF Full Text Request