A collaborative research team from the Korea Institute of Materials Science (KIMS) has developed a groundbreaking carbon coating technology specifically designed to address the corrosion and wear issues faced by marine metals used in ammonia-powered vessels. Led by Dr. Young-Jun Jang and Dr. Jongkuk Kim, in partnership with Dr. Sungmo Moon’s team, this innovation is poised to accelerate the commercialization of eco-friendly shipping solutions.
The newly developed technology offers a solution to the severe degradation that conventional marine materials, such as stainless steel 440C, experience when exposed to the highly alkaline and chemically reactive nature of ammonia fuel. These materials tend to suffer from the breakdown of surface oxide layers, leading to localized corrosion and wear, particularly in critical components like engines, valves, and pumps. As such, the need for robust corrosion-resistant surface technologies has become essential in the design and certification processes for ammonia-powered ships.
By employing a carbon coating technology known as ta-C:Hx, the research team has achieved significant advancements in protecting metals from corrosion in ammonia environments. Experimental data reveals that while traditional marine materials exhibit corrosion current densities of approximately 48 μA/cm2 in ammonia solutions, the new coating reduces this figure to 4 μA/cm2, marking a remarkable 92% reduction. Furthermore, the corrosive wear rate has decreased dramatically from 1.4 × 10-6 mm3/N·m for conventional materials to 1.3 × 10-8 mm3/N·m with the new coating, representing an impressive 99.1% reduction in tribocorrosion.
Traditional coatings, such as nitride layers and wet plating, have been optimized for different marine environments, but their effectiveness in ammonia has not been sufficiently validated. These coatings often suffer from issues like porosity and thickness inconsistencies, which can create vulnerabilities in corrosive settings. The innovative aspect of the new carbon coating technology lies in its specific engineering for ammonia environments. By utilizing pulsed bias control in a filtered arc deposition process, the research team successfully minimized defects that could initiate corrosion, resulting in a stable and effective carbon structure that withstands corrosion reactions in aqueous ammonia solutions.
This technology is the first of its kind developed in South Korea that meets the corrosion resistance standards required for ammonia-powered vessel design and certification. In line with the 2023 IMO Greenhouse Gas Reduction Strategy, the International Maritime Organization (IMO) mandates a transition to zero-carbon fuels in international shipping by 2030. The Maritime Safety Committee has also approved guidelines requiring the verification of corrosion resistance in the fuel systems of ammonia-fueled ships.
Countries such as Japan, Norway, and Singapore are actively conducting demonstration projects to assess the performance of ammonia-powered vessels. South Korea has recognized ammonia-powered ships as a strategic sector within its shipping and shipbuilding industries, as outlined in the 2050 Green Shipping National Action Plan and the K-Ammonia Eco-Friendly Ship Promotion Strategy. Despite securing Approval in Principle (AiP) for ammonia-powered vessel designs, domestic shipbuilders have faced challenges due to a lack of reliable surface coating technologies for corrosive environments.
The development of this new coating technology builds on KIMS’s extensive expertise in carbon coatings and environmental corrosion evaluations. It showcases significant technological competitiveness in meeting the stringent corrosion resistance requirements necessary for ammonia fuel systems. Dr. Young-Jun Jang, the principal researcher and lead investigator, emphasized the practical implications of this technology, stating, “If this technology is commercialized, it will provide a solution for long-distance operation by significantly improving the efficiency and reliability of key components for eco-friendly shipbuilding.”
Co-researchers Dr. Jongkuk Kim and Dr. Sungmo Moon highlighted the importance of the collaborative approach taken during research, which utilized KIMS’s internal technologies and infrastructure rather than relying on external solutions. They expect this advancement to enhance the domestic industrial ecosystem and expand into global markets.
This research was supported by KIMS’s in-house program, “Development of Practical Tribology Technologies for Cryogenic Environments,” and funded by the National Research Foundation of Korea (NRF) through the Nano and Materials Technology Development Program. The findings were published online on December 1, 2025, in the journal Carbon, which has an impact factor of 11.6.
Currently, the research team is focusing on stabilizing the coating process and conducting reliability assessments for ammonia fuel environments while pursuing additional patent applications. They plan to explore technology transfer and commercialization opportunities in collaboration with industry partners.
