Acoustic Emission Behavior of 12MnNiVR under Corrosion

Abstract

Large atmospheric storage tanks play an important role in the petrochemical, energy, and logistics industries. Improvements in materials and manufacturing processes have enabled larger tank volume capacity, leading to increased material performance requirements as well. 12MnNiVR is a material typically used in the fabrication of large-scale atmospheric tanks. However, serious tank bottom corrosion can occur, not only from the medium inside the tank, but also from soil erosion of the tank foundation. Testing of corrosion on the tank floor is usually conducted using nondestructive methods such as magnetic flux leakage (MFL) to determine an equivalent bottom corrosion indication, but this requires cleaning of the tank and access to a large area for inspection, which is costly. In recent years, acoustic emission (AE) testing methods have been frequently used to determine the qualitative corrosion condition of the tank floor. However, according to researchers, only a few simple parameters of AE signals, tank bottom corrosion severity grade, the lack of concrete storage tank under the conditions of material effect, corrosion materials research AE signal spectrum and characteristic parameters, and thus the corrosion status of materials for quantitative analysis and assessment. This study simulates corrosion conditions for 12MnNiVR, a typical material used in the construction of atmospheric tanks. The Devanathan–Stachurski technique is used, with electrolytic hydrogen charging corrosion on one side of the surface material and simulated soil solution soaking on other. AE signals were collected and analyzed over time under corrosive conditions, and the empirical mode decomposition (EMD) and Hilbert–Huang transform (HHT) methods of signal processing were used to obtain AE signal characteristics from the beginning to various stages of corrosion, providing an experimental basis for online AE measurement and qualitative assessment of large atmospheric tanks.