| Titre : | Oxidation protection of Ni-base superalloys by halogen treatment (2011) |
| Auteurs : | H.-E. Zschau, Auteur ; P. J. Masset, Auteur ; M. Schutze, Auteur |
| Type de document : | Article : texte imprimé |
| Dans : | Materials and corrosion (Vol. 62 N° 7, Juillet 2011) |
| Article en page(s) : | pp. 687–694 |
| Note générale : | Génie Mécanique |
| Langues : | Anglais |
| Index. décimale : | 620.1 (Essais des matériaux. Défauts des matériaux. Protection des matériaux) |
| Tags : | Borderline materials Halogen effect Ion implantation Ni-base superalloys Protective alumina scale |
| Résumé : |
A new concept of oxidation protection is proposed for Ni-base alloys with Al-amounts of 2–5 wt%. Following Wagner's theory of oxidation the formation of a dense protective alumina scale is possible if the Al-activity is sufficiently high. This condition can be fulfilled by using the halogen effect. Thermodynamical calculations reveal the existence of regions for a positive effect of F and Cl for the alloys IN738 and IN939. In the case of fluorine these results are transformed into F concentrations in a screening by using ion implantation. By the F-effect the oxidation mechanism at 1050 °C/air was changed from internal oxidation of Al to an external formation of an Al2O3 – scale. Optimal implantation parameters were defined. The formation and stability of the protective alumina scale was proved within 1000 h/1050 °C.
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| DEWEY : | 620.1 |
| ISSN : | 0947-5117 |
| En ligne : | http://onlinelibrary.wiley.com/doi/10.1002/maco.201005879/abstract |
