Corrosion Behavior and Life Prediction of A Newly Developed Train Body Steel S500AW in Outdoor Atmospheric Environment

The early corrosion behavior of newly developed train body steel S500AW and traditional Q450NQR1 steel and Q345B steel for comprision was studied by atmospheric exposure test combined with indoor accelerated corrosion test. The corrosion morphology and corrosion product composition on surface of the sample before and after the test were analyzed by scanning electron microscopy ( SEM ) and Raman spectrometer. The results showed that the surface of S500AW steel was smoother and cleaner in the early stage of exposure in Beijing atmospheric environment, with only a small amount of dust particles attached, and the corrosion resistance was better. The corrosion product was Fe₂O₃ and some γ-FeOOH. With the extension of corrosion time, the content of γ-FeOOH increased gradually, and the corrosion resistance of steel increased gradually. Based on the data of corrosion mass loss, the corrosion test method and corrosion life prediction model of steel for railway vehicle body were established. Through the grey correlation analysis method, the good correlation between periodic wetting test and outdoor natural environment atmospheric exposure test was confirmed.