Study on the effects of hydrostatic pressure, temperature and oxygen content on the electrochemical corrosion of 20# steel

Purpose The corrosion mechanism of metals, particularly in oil and gas pipelines, is intricate due to the coupling effects of hydrostatic pressure, temperature and oxygen content. Using 20# steel as the subject, this study aims to delve into the impact of these coupling effects on its dissolution in chloride-containing solutions through various methods. Design/methodology/approach In situ electrochemical testing, weight loss testing, micromorphology characterization, finite element methods and orthogonal experiments were conducted to investigate the self-corrosion mechanism of 20# steel in this complex environmental system. Findings Key findings reveal that the corrosion potential of 20# steel decreases with increasing hydrostatic pressure, decreasing oxygen content and rising temperature. In this complex environment, temperature exerts the most significant impact on corrosion weight loss, followed by hydrostatic pressure, while the influence of oxygen content is less pronounced, aligning with electrochemical results. Originality/value This paper systematically studies the impact of multiple environmental factors commonly found in oil pipeline on the corrosion rate of low-carbon steel, providing a new research method for studying metal corrosion in complex environments, especially those involving high hydrostatic pressure.