DLC coatings in high temperature hydrogen sulfide environment

Surface protection in high temperature hydrogen sulfide environment remains a significant challenge with limited number of materials providing adequate protection. Diamond-like carbon (DLC) thin films are recognized across different sectors as a promising way of controlling wear and the corrosion performance of components. The aim of this paper is to test the hypothesis that thin DLC coatings may act as an efficient corrosion barrier for steel components in high temperature hydrogen sulfide environment. The DLC coating was deposited in this work using Plasma-Enhanced Chemical Vapor Deposition (PECVD) process and the coating was characterized in terms of the structure morphology and mechanical properties. Coated test coupons were exposed to high pressure high temperature tests simulating sour production environments for the period of 28 days. The performance of DLC coating was compared with data obtained from a large tank lining joint industry project focusing on tank lining study previously completed by one of the authors.