Interaction between pitting corrosion and critical flow velocity for erosion-corrosion of 304 stainless steel under jet slurry impingement

摘要

The interaction between pitting corrosion and critical flow velocity (CFV) for erosion-corrosion of 304 stainless steel under slurry impingement was investigated through electrochemical tests, scanning electron microscopy and X-ray photoelectron spectroscopy. The results show that pitting corrosion affects the precise determination of CFV using the potentiostatic polarization tests, while CFV just corresponds to the case of the highest pitting corrosion resistance in erosion-corrosion process. This interaction is explained in terms of the properties of surface film. Furthermore, the guidance for quick determination of CFV is proposed and the significance of CFV in evaluating the erosion-corrosion resistance is highlighted.