Van der Merwe, Josias WillemDu Toit, MadeleineKlenam, D.E.P.Bodunrin, M.O.2022-11-232022-11-232022-09Van der Merwe, J.W., Du Toit, M., Klenam, D.E.P. et al. 2022, 'Fracture mechanics of carbon steel under different carbon monoxide and dioxide gas mixture conditions in water', Scientific African, vol. 17, art. e01355, pp. 1-8, https://doi.org/10.1016/j.sciaf.2022.e01355.2468-2276 (online)10.1016/j.sciaf.2022.e01355https://repository.up.ac.za/handle/2263/88459The results of carbon steel stress-corrosion cracking experiments in a CO-CO2-H2O environment at varying gas mixtures are presented. The fracture mechanics of carbon steel were investigated in distilled water under CO-CO2 combinations of various compositions. For each mixture, the subcritical rates of crack propagation and thresholds for stress intensity were established. Using an applied electrochemical potential, the effects of cathodic and anodic polarization on carbon steel were examined. At a low-stress intensity threshold of 3 MPa√m, cracking was caused in a 50% gas mixture. The stress intensity threshold was double that of the 50%CO. Low dissolved oxygen content was reported at 1% CO, with a threshold of 15 MPa√m. As a result, increasing CO had the opposite effect on the stress intensity threshold. Cathodic polarization reduced the susceptibility to cracking and the growth rates of subcritical cracks ranged from 10−10 to 10−9 ms−1. The underpinning stress corrosion mechanisms are investigated further, as well as their consequences in different CO-CO2-H2O environments.en© 2022 The Author(s). Published by Elsevier B.V. on behalf of African Institute of Mathematical Sciences / Next Einstein Initiative. This is an open access article under the CC BY license.Stress-corrosion crackingCarbon steelCarbon monoxide (CO)Carbon dioxideFracture mechanicsCrack growth rateStress intensity thresholdEngineering, built environment and information technology articles SDG-06SDG-06: Clean water and sanitationEngineering, built environment and information technology articles SDG-09SDG-09: Industry, innovation and infrastructureEngineering, built environment and information technology articles SDG-12SDG-12: Responsible consumption and productionEngineering, built environment and information technology articles SDG-13SDG-13: Climate actionArticle