Abstract
Many studies have shown that a phosphoric-acid treatment improves the high temperature oxidation resistance in air of some alloys. Interestingly, though, the phosphoric-acid treatment generates a structural modification of the steel surface which is catastrophic for the high-temperature oxidation behavior at 1,000 °C. The aim of our work was to test the effect of a reactive element sol–gel coating on high-temperature oxidation resistance of phosphoric acid-treated AISI 304 steel. The oxide scale growth mechanisms were studied by exposing La-coated and uncoated phosphoric acid-treated 304 steel samples to high-temperature conditions in air. A phosphoric-acid treatment modified the structural composition and the surface morphology of the AISI 304 steel by the formation of a FeH2P3O10 structure, leading to hematite formation and to a breakaway phenomenon. Lanthanum coating, after initial phosphoric-acid treatment, led to the formation of LaCrO3 which limited through-scale cracking and reduced the growth of iron oxides.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
