| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 7988226 | Intermetallics | 2018 | 8 Pages |
Abstract
The effect of yttrium on the microstructure and high-temperature oxidation performance of Nb-15Si-24Ti-4Cr-2Al-2Hf (at.%) alloys was investigated. Alloys containing different yttrium contents were designed, aiming at maximizing the beneficial effect of yttrium addition and avoiding the possible adverse effect of over-doped yttrium. Results showed that Y was primarily partitioned in γ-Nb5Si3, relative to Nb solid solution (Nbss), Nb3Si and α-Nb5Si3. Microstructural refinement and oxidation resistance enhancement were achieved by yttrium addition up to 0.3â¯at.%, accompanied by the transition towards parabolic oxidation kinetics. An adverse effect of over-doped yttrium (0.5â¯at.% addition) by coarsening the microstructure and deteriorating the oxidation resistance was confirmed. A relatively continuous glassy SiO2 layer was generated in the oxide scale formed on the Y-containing alloys with enhanced oxidation resistance.
Related Topics
Physical Sciences and Engineering
Materials Science
Metals and Alloys
Authors
Yueling Guo, Lina Jia, Huarui Zhang, Fengxiang Zhang, Hu Zhang,