Influence of atmosphere in heating furnace on oxidation behavior of SUS304 stainless steel

The aim of this paper is to determine the optimum heating technique by studying oxide scale morphology, oxide scale/matrix interface, the thickness of oxide scale and adhesive force between the oxide scale and matrix, therefore reliable basis tor rolling and descaling process could be obtained. Oxidation experiment was undertaken in the atmosphere furnace, designed by ourselves. The oxide scale/matrix interlaces were captured and the thicknesses ol the oxide scale were measured. Scratch method, carried out on UMT-2, was used to measure the adhesive force. The results indicated that the scale/matrix interface is found to be corrugated, however no non-contact zone is observed. This means the oxide scale is protective to the matrix. In else same condition ol oxidation, the curve ol oxide scale thickness-time represented the shape of parabola approximately. Increase of temperature and percentage content of oxygen can result in increase of the thickness of the oxide scale. The maximum thickness reaches to 99.19 μm, when the temperature is 1250°C and the holding time is 3h. The existence of water vapor can aggravate the oxide processing significantly and make the scale thickness increase by 30.12 μm. The holding time is a critical factor, which influences adhesive force of SUS304, and it increases with the increase of holding time.