Duarte Martinez, FabianSyed, AdnanDawson, K.Tatlock, G. J.Morar, N. I.Kothari, M.Tang, C.Leggett, J.Mason-Flucke, J. C.Gibson, G.Nicholls, Nicholls, John R.Gray, SimonCastelluccio, Gustavo M.2023-05-182023-05-182023-05-01Duarte Martinez F, Syed A, Dawson K, et al., (2023) Effect of NaCl and SO2 on the stress corrosion cracking of CMSX-4 at 550°C. Materials at High Temperatures, Volume 40, Issue 4, August 2023, pp. 283-2950960-3409https://doi.org/10.1080/09603409.2023.2205760https://dspace.lib.cranfield.ac.uk/handle/1826/19669In the pursuit of more efficient gas turbine engines, components are required to operate for longer times at elevated temperatures. This increased time in service, together with a complex loading regime, can expose the material to environmental attack. This work has demonstrated that the interaction of stress, NaCl and a sulphur-containing environment is critical to cause crack initiation in the early stages of the exposure and accelerated corrosion rates in CMSX-4 at 550°C. The effect of having small concentrations of moisture in the gaseous environment or as water crystallisation in the salt is still to be investigated. A working hypothesis is that the interaction of alkali chlorides with a sulphur-containing atmosphere is the trigger to a self-sustaining cycle where metal chloride formation, vaporisation and oxidation lead to high amounts of hydrogen injection in a rapid manner and, therefore, hydrogen embrittlement.enAttribution 4.0 Internationalcmsx-4c-ringhot corrosionfactsage 8.1Article