Roles of Alloying Elements on the Corrosion Behavior of Amorphous W–Zr–(15–33)Cr Alloys in 1 M NaOH Solution
Roles of alloy-constituting elements on the corrosion behavior of the sputter-depositedamorphous W-Zr-(15-33)Cr alloys was studied in 1 M NaOH solution open to air at 25°Cusing corrosion tests and open circuit potential measurements. Zirconium and chromiummetals act synergistically with tungsten in enhancing the corrosion resistance of the sputterdepositedamorphous W-Zr-Cr alloys containing 15-33 at % chromium content so as toshow higher corrosion resistance than those of alloy-constituting elements in 1 M NaOHsolution. The corrosion rates of the amorphous W-Zr-(15-33)Cr alloys containing 9-33 at %tungsten are in the ranges of 2.0-5.0×10-3 mm.y-1 after immersion for 240 h in 1 M NaOHsolution which is about two orders of magnitude lower corrosion rates lower than that oftungsten and even slightly lower than that of the zirconium metal. The simultaneousadditions of zirconium and chromium metals in W-Zr-(15-33)Cr alloys are effective forennoblement of the open circuit potential of the tungsten metal.Keywords: W-Zr-Cr alloys, corrosion resistance, immersion test, open circuit potential, 1 MNaOH.DOI: 10.3126/jncs.v25i0.3312Journal of Nepal Chemical Society Volume 25, 2010 pp 93-100