MoSiB alloys show promise as the next-generation turbine blade material due to their high-temperature strength and oxidation resistance afforded by a protective borosilicate surface layer. Powder processing and reactive synthesis of these alloys has proven to be a viable method and offers several advantages over conventional melt processing routes. Microstructures obtained have well-dispersed intermetallics in a continuous matrix of molybdenum solid-solution (Mo-ss). However, bend testing of pure Mo and Mo-ss samples has shown that, while the powder processing route can produce ductile Mo metal, the hardening effect of Si and B in solid-solution renders the matrix brittle. Testing at elevated temperatures (200°C) was performed in order to determine the ductile-to-brittle transition temperature of the metal as an indication of ductility. Methods of ductilizing the Mo-ss matrix such as annealing and alloying additions have been investigated.
| Identifer | oai:union.ndltd.org:GATECH/oai:smartech.gatech.edu:1853/16293 |
| Date | 16 May 2007 |
| Creators | Rockett, Chris H. |
| Publisher | Georgia Institute of Technology |
| Source Sets | Georgia Tech Electronic Thesis and Dissertation Archive |
| Detected Language | English |
| Type | Thesis |
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