The oxidation behavior of Cu 50Zr 50 and Cu 46Zr 46Al 8 glasses during continuous heating up to 1073 K has been investigated, with special emphasis on the oxidation resistance in the supercooled liquid (SCL) state. For Cu 50Zr 50, the oxide layer mostly consists of monoclinic ZrO 2 (m-ZrO 2), while for Cu 46Zr 46Al 8, the oxide layer consists of two different layers: an outer layer consisting of tetragonal ZrO 2 (t-ZrO 2) + Al 2O 3 + metallic Cu (oxidation product from the SCL state of the glass matrix) and inner layer comprised of m-ZrO 2 + metallic Cu islands (oxidation product from the crystallized matrix). Cu-enriched regions consisting of Cu 51Zr 14 (in Cu 50Zr 50) or AlCu 2Zr + Cu 70Zr 15Al 15 + Cu 51Zr 14 (in Cu 46Zr 46Al 8) are present below the oxide layer. The present study shows that the addition of Al (8 at.%) in Cu 50Zr 50 results in a significant deterioration of the oxidation resistance in the SCL state since the solutionizing of Al in t-ZrO2 leads to a higher oxygen ion vacancy concentration, thus providing a higher activity of oxygen ions.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering