CorroZoom webinar: Corrosion Protection in Deep Sea Environments

The next CorroZoom webinar will be on 20 May and will be given by Prof. Li Liu from Northeastern University in Shenyang, China. The talk is entitled “Corrosion Protection in Deep Sea Environments.” She has found some really interesting corrosion behavior in the deep sea environment. Please register and attend if you are interested by clicking here.

Corrosion Protection in Deep Sea Environments

By Li Liu, Northeastern University, China

Abstract
The deep sea, defined as ocean regions exceeding depths of 200 meters, covers approximately 60% of the Earth’s surface and has become a critical frontier for scientific exploration and resource extraction. Unlike shallow waters, the deep-sea environment presents a unique set of challenges characterized by extreme hydrostatic pressure, low temperature, depleted dissolved oxygen level, and darkness. These factors lead to distinct corrosion failure behaviors in structural metals and coatings compared to those observed in surface environments. This presentation synthesizes over a decade of research into the corrosion mechanisms of key structural materials, including high-strength low-alloy steels, copper alloys, and titanium alloys, as well as the degradation of protective organic coatings. A central finding of this work is that, at the same temperature and oxygen contents, hydrostatic pressure significantly accelerates metal corrosion, regardless of whether the material undergoes active dissolution or passivation. We found that hydrostatic pressure may thin the Helmholtz layer of the electrochemical reaction, which is a key factor in enhanced metal dissolution rates under extreme hydrostatic pressure. Furthermore, high hydrostatic pressure increases the stress corrosion cracking sensitivity and reduces the fatigue life of titanium alloys. The synergistic effect of hydrostatic pressure and cyclic loading disrupts the density and uniformity of passive films, facilitating penetration of corrosive media and promoting crack initiation. A novel deep-sea passivation protective coating has been developed to combat these challenges and enhance the stability of titanium alloys in the harsh deep-sea environment.

Bio
Li Liu is a Professor at the Corrosion Protection Center and the National Key Laboratory of Digital Steel at Northeastern University (NEU), China. She earned her Ph.D. in 2007 at the State Key Laboratory for Metal Corrosion and Protection at the Institute of Metal Research (IMR), Chinese Academy of Sciences and subsequently spent over a decade working there before joining NEU in 2018. Professor Liu’s research is dedicated to understanding and mitigating metal corrosion in extreme and harsh marine environments, with a primary focus on deep-sea conditions, high-temperature marine interfaces, and island-based infrastructure. Her work bridges fundamental electrochemistry with practical materials engineering, contributing significantly to the durability of assets in the world’s most challenging aquatic frontiers. She has published over 130 papers with ~6,000 citations and an h-index of 47 (Jan 2025).