Corrosion behavior of 300M steel in three area-to-volume ratio simulated water environments

The corrosion of 300M steel in gap water produced in airplane structure parts is a big problem. The influence of the area-to-volume ratio on the corrosion behavior of 300M steel in simulated water is studied by evaluating the weight loss, corrosion rate, damage degree, dissolved oxygen and pH value of the solution with Tafel test and electrochemical impedance spectrum. The results indicate that with the process of corrosion the content of dissolved oxygen is reduced while the pH value rises in all the three different area-to-volume solutions (2, 5, 20 mL/cm²). The greater the area-to-volume ratio is, the greater is the weight loss and corrosion rate. Tafel test and electrochemical impedance spectrum show that the corrosion resistance differences of 300M ultra-high strength steel lead to different corrosion degrees in the three different area-to-volume ratio solution environments, and the corrosion rate relationship is V₂₀>V₅>V₂.