Abstract
Passive and transpassive films on FeCr alloys containing 5 – 6% chromium in 1 mol l −1 Na 2SO 4 solutions of pH 2 and pH 6 have been investigated by in situ ellipsometry coupled with electrochemical measurements. The optical constants of film-free surfaces of the alloys, which were determined by ellipsometry in dehydrated methanol immediately after stripping the surface films in a bromine-methanol solution, were used in the calculation of the thickness and optical constants of these films. It was found that the thickness and the real parts of the optical constants of the films decreased with increasing chromium content of the alloy and decreasing pH of the solution. In the case of the passive films this was most pronounced for chromium contents in the range 5–20% which indicates the occurrence of substantial variations in the nature and composition of the films. The transpassive film thickness, the rate of film growth with the potential and the real part of the optical constant were usually found to be larger than those of the passive films.
Sign-in/Register to access full text options 
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.
