Abstract
The influence of the F − ions containing compounds: NaF, HBF 4, H 2SiF 6, NH 4F·HF and their concentrations on formation of phosphate coatings on Al in МоО 4 2− ions containing solutions, as well as protective properties of the phosphate coatings in a 0.5 M Na 2SO 4 solution have been studied. The studies of film composition by the XPS method have shown, that the phosphate coating consists of the metal phosphates from aluminium alloy and the Mo (IV, V) phosphates, which are formed during reduction of МоО 4 2− ions. The mass of phosphate layer and that of etched metal depend on the nature of fluoride ions, which can be arranged in the following order according to the decrease in strength of their influence: H 2SiF 6 > NH 4F·HF > HBF 4 > NaF. Polarization measurements in a 0.5 M Na 2SO 4 solution and the calculated electrochemical parameters testify that phosphated Al samples exhibit a lower corrosion rate and a higher corrosion resistance as compared to non-phosphated Al substrate.
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.
