Erosion-corrosion behaviors of 1045 and J55 steels in crude oil

摘要

The erosion-corrosion behaviors of 1045 and J55 steels in crude oil with a variation in sand sizes between 500 and 2000 mu m were studied using the impingement jet system incorporated with an electrochemical measurement and were characterized with a scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and an inductively couple plasma-optical emission spectrometer (ICP-OES). All the erosion-corrosion results agreed well with the ICP-OES measurement that the released iron ions increase with the high wastage of steels, particularly for the 1045 steel, which showed a greater number of released iron ions and a higher penetration rate than the J55 steel. The degree of synergism between the erosion and corrosion drastically changed with the impingement sand size and the microstructure of the steels. The XPS results showed a notable correlation between the erosion-corrosion behaviors and the compounds generated after the wastage of the specimens. A high atomic percentage (at%) of SiO2 and the high amount of C-O-C + C=0 were found on the highly degradedsurface. Classification of the degradation mode was made distinct by considering the Fe(II)/Fe(III) atomic ratio. A high ratio of the Fe(II)/Fe(III) compounds represents better pure erosion resistance, whereas a low ratio demonstrates better pure corrosion resistance and total corrosion component resistance.