Stress Corrosion Cracking Resistance of Metallic Materials Used in Drilling Technology – Part 2: Test Methodology for Assessing Susceptibility in Drilling Environments

Due to the large impact on tool integrity and reliability, assessing susceptibility to avoid environmentally assisted cracking including stress corrosion cracking (SCC) is in many cases more relevant for the design than the mechanical properties of manufacturing materials used in drilling tools that are subjected to high mechanical loads while in permanent contact with the drilling fluid. Consequently, an assessment of the SCC susceptibility of metallic materials used in drilling tools is very relevant for design. In part 1, the influence of temperature, oxygen content and chloride concentration on the SCC susceptibility of austenitic stainless steels and UNS N07718 was studied using constant load testing (CLT). CLT, however, implies long-term testing and might involve large series of experiments to determine SCC susceptibility. In this study, a test methodology based on slow strain rate (SSR) testing was evaluated for assessing the SCC resistance of metallic materials commonly used in drilling technology. SSR-tests were conducted on several austenitic stainless steels in a simulated drilling environment, and the results, which demonstrated the feasibility of using this methodology are discussed.