Abstract
Short-term cyclic oxidation tests were performed at 1200°C and 1500°C on β-NiAl with 1 vol% oxide dispersions of Y2O3, La2O3 and Al2O3. The Y2O3 addition resulted in a very adherent α-Al2O3 scale at 1200°C, with some improvement in the scale adhesion at 1500°C, compared to an undoped β-NiAl alloy. The La2O3 and Al2O3 additions resulted in more severe oxidation than the undoped β-NiAl at 1200°C. Both Y and La ions are found to segregate to α-Al2O3 scale grain boundaries using scanning transmission electron microscopy/energy dispersive x-ray analysis. However, at both 1200°C and 1500°C, the La addition appears to cause a rapid increase in the isothermal oxidation rate, leading to excessive scale spallation.
Original language | English |
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Pages (from-to) | 987-992 |
Number of pages | 6 |
Journal | Materials Research Society Symposium - Proceedings |
Volume | 364 |
Issue number | 2 |
State | Published - 1995 |
Event | Proceedings of the 1994 MRS Fall Meeting - Boston, MA, USA Duration: Nov 28 1994 → Nov 30 1994 |