Comparing the pitting corrosion behavior of prominent Zr-based bulk metallic glasses

Gespeichert in:

Personen und Körperschaften:	Gostin, Petre Flaviu, Eigel, Dimitri, Grell, Daniel, Eckert, Jürgen, Kerscher, Eberhard, Gebert, Annett, Scudino, S., Yang, C., Eckert, J.
Titel:	Comparing the pitting corrosion behavior of prominent Zr-based bulk metallic glasses
Format:	E-Artikel
Sprache:	Englisch
veröffentlicht:	Cambridge Cambridge University Press 2015 Online-Ausg.. 2020
Gesamtaufnahme:	, 30,2015,2
Schlagwörter:	Lochfraßbildung Rasterelektronenmikroskopie Repassivierungspotenzial Pitmorphologie Pitting Scanning Electron Microscopy Repassivation Potential Pit Morphology
Quelle:	Qucosa

Details
Zusammenfassung:	Five well-known Zr-based alloys of the systems Zr–Cu–Al–(Ni–Nb, Ni–Ti, Ag) (Cu 5 15.4–36 at.%) with the highest glass-forming ability were comparatively analyzed regarding their pitting corrosion resistance and repassivation ability in a chloride-containing solution. Potentiodynamic polarization measurements were conducted in the neutral 0.01 M Na₂SO₄ 1 0.1 M NaCl electrolyte and local corrosion damages were subsequently investigated with high resolution scanning electron microscopy (HR-SEM) coupled with energy dispersive x-ray spectroscopy (EDX). Both pitting and repassivation potential correlate with the Cu concentration, i.e., those potentials decrease with increasing Cu content. Pit morphology is not composition dependent: while initially hemispherical pits then develop an irregular shape and a porous rim. Corrosion products are rich in Cu, O, and often Cl species. A combination of low Cu and high Nb or Ti contents is most beneficial for a high pitting resistance of Zr-based bulk metallic glasses. The bulk glassy Zr₅₇Cu₁₅.₄Al₁₀Ni₁₂.₆Nb₅ (Vit 106) and Zr₅₂.₅Cu₁₇.₉Al₁₀Ni₁₄.₆Ti₅ (Vit 105) alloys exhibit the highest pitting resistance.