In this paper, the erosion-corrosion behaviours of BFe30-1-1 in artificial sea water with an without addition of sand have been studied by rotating cylinders erosion-corrosion testing apparatus. The methods adopted in this study include weight loss test, electrochemical measurement such as electrochemical impedance spectrum(EIS), cyclic linear polarization, SEM, EDX, In addition, the inhibition effect of BTA on the erosion-corrosion of BFe30-1-1 has been investigated. In single phase artificial sea water, the transfer electron number of BFe30-1-1 during the course of erosion nd corrosion was calculated to be nearly one. The linear polarization constant(B) increased with increasing fluid velocity. The results obtained from cyclic polarization measurement showed that BFe30-1-1 has a sensitivity of local corrosion for fluid velocity less than 2m/s, however, the sensitivity disappeared for fluid velocity more than 2m/s. According to EIS measurement results, the erosion-corrosion of BFe30-1-1 was controlled by diffusion when fluid velocity was below 2m/s. Furthermore, i can be seen from the photographs of SEM that there exit many waves in axis direction on metal surface for low fluid velocity (<2m/s), however, the waves in same direction can not be found for high fluid velocity(>2m/s). On the basis of above experimental results, it is concluded that there is an experimental results, it concluded that there is a critical velocity of 2m/s for erosion and corrosion of BFe30-1-1 in artificial sea water. In sand containing artificial the water, the results of weight loss test and EIS measurement showed that the action of corrosion on erosion approached a limit when the sand content was higher than 1%, at this time the metal surface had an ulcer morphology. The inhibitor BTA can impress the erosion and corrosion of BFe30-1-1 greatly, especially in nonstatic artificial sea water. BTA still has a good inhibition performance for BFe30-1-1 in the solution with high sand content. All of these can be attributed to the strong interaction between BTA and BFe30-1-1, which reduces the corrosion of BFe30-1-1 and the accelerated action of corrosion on erosion.
修改评论