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The effect of 0.1 atomic percent zirconium on the cyclic oxidation behavior of beta-nial for 300 hours at 1200 c
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Barrett, C. A. |
| Copyright Year | 1988 |
| Description | The long time effect of 0.1 at percent Zr (0.2 wt percent Zr) on the cyclic oxidation behavior of hipped beta-NiAl was studied. Oxidation testing was performed in static air at 1200 C for up to 3000 one-hour exposure cycles. Specific weight change versus time data was modeled with the COSP computer program to analyze cyclic oxidation behavior. The Zr-free stoichiometric alloy oxidized and spalled randomly to bare metal between cycles at a rate high enough to deplete Al to a low enough level that oxidation breakaway took place as nonprotective NiO replaced the alpha-Al2O3/NiAl2O4 scale as the controlling oxide. The Zr minimized this severe type of spalling maintaining the protective alpha-Al2O3 scale even out to 3000 hours for the stoichiometric alloy with no significant Al depletion. A third beta-NiAl alloy containing 0.1 at percent Zr but with 10 percent less Al than the stoichiometric alloy was also tested and showed some depletion of Al, but the protective Al2O3/NiAl2O4 was still maintained to close to 2700 hours. |
| File Size | 1029320 |
| Page Count | 20 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_19890004195 |
| Archival Resource Key | ark:/13960/t88h3hm9d |
| Language | English |
| Publisher Date | 1988-01-01 |
| Access Restriction | Open |
| Subject Keyword | Metallic Materials Aluminides Stoichiometry Zirconium Nickel Alloys Spalling Oxidation Mathematical Models Protective Coatings Computer Programs Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Article |
