Abstract

A series of nanocrystalline or amorphous single solid solutions of W-Ta alloys are prepared by D.C. magnetron sputtering. The passivation behavior of these alloys is studied by immersion test, electrochemical measurements and X-ray photoelectron spectroscopy (XPS) analysis. The W-Ta alloys are passivated spontaneously and show significantly high corrosion resistance in 12 M HCl at 30 °C. Their corrosion rates are about two orders of magnitude lower than that of sputter-deposited tungsten and are lower than that of sputter-deposited tantalum. XPS analysis shows that tantalum is concentrated in both the air-formed films and the passive films formed spontaneously on the alloys after long time immersion in 12 M HCl. The surface films are composed of double oxyhydroxides of Ta 5+ and W 4+ ions. The formation of spontaneous passive film composed of a double oxyhydroxide of tungsten and tantalum ions is responsible for high corrosion resistance of the W-Ta alloys in concentrated hydrochloric acid solution.

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 call

Disclaimer: 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.