IMPROVED OXIDATION RESISTANCE OF MOLYBDENUM BY ALLOYING WITH RARE EARTH AND OTHER SELECTED METALS
Abstract
A new method of forming a protective oxide scale on Mo-Hf and Mo-Yt alloys has bee introduced by using a combina ion of selective oxidation and sacrificial oxidation. Oxidatio experiments were carried out at 725 C on binary Mo alloys containing 2.6 At-% Yt and 5.6 At-% Hf in which the Yt and the Hf had been selectively oxidized by a process of internal oxidation. These experiments were successful in producing a continuous internal scale from whic he ou r layer of Mo w s t en removed by volatilization as MoO3. Although a continuous scale as produced in this manner with the 5.6 At-% Hf alloy it was not comple ely a her n . It peeled in some places and was quite adherent in others. With 2.6 t-% Yt the specimen became coated with a liquid oxide mixture at 725 C, indicating the formation of a low melting point eutectic. A technique for selective oxidation of Mo-Hf alloys in a He atmosphere was developed. The introduction of O from the furnace refrac ori s and other similar sources was eliminated. Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 27, 1962
- Accession Number
- AD0282638
Entities
Organizations
- Colorado School of Mines