Corrosion Science · 2018 · 72 citations · 18 references
Natural SciencesMaterials EngineeringMaterials ScienceCorrosion ScienceMetallic MaterialsMetallurgyCorrosion EngineeringCorrosion MechanismsCorrosion-resistant MaterialsHigh-temperature CorrosionHigh-temperature OxidationStress Corrosion CrackingChemical Reaction MechanismsCorrosion ProductsHigh-resolution Electron MicroscopyHigh-resolution Transmission Electron MicroscopyOxidation Of Titanium AlloysOxygen EnrichmentTitanium Alloy CorrosionTitanium Alloys
Hot salt stress corrosion cracking in Ti 6246 alloy has been investigated to elucidate the chemical mechanisms that occur. Cracking was found to initiate beneath salt particles in the presence of oxidation. The observed transgranular fracture was suspected to be due to hydrogen charging; XRD and high-resolution transmission electron microscopy detected the presence of hydrides that were precipitated on cooling. SEM-EDS showed oxygen enrichment near salt particles, alongside chlorine and sodium. Aluminium and zirconium were also involved in the oxidation reactions. The role of intermediate corrosion products such as Na2TiO3, Al2O3, ZrO2, TiCl2 and TiH are discussed.
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