Subtask 6.6 - SiAION Coatings for Alkali-Resistant Silicon Nitride. Topical report
The efficiency of a gas turbine can be improved by increasing operating temperature. Construction materials should both meet high strength requirements and exhibit hot alkali corrosion resistance. Structural ceramics based on silicon nitride are promising candidates for high temperature engineering applications because of their high strength and good resistance to corrosion. Their performance varies significantly with the mechanical properties of boundary phases which, in turn, depend on their chemical composition, thickness of the amorphous phase, and the deformation process. To make silicon nitride ceramics tough, SiAlON ceramics were developed with controlled crystallization of the amorphous grain boundary phase. Crystallization of the grain boundary glass improves the high temperature mechanical properties of silicon nitride ceramics. Thus, the knowledge of silicon oxynitride ceramics corrosion behavior in Na{sub 2}SO{sub 4} becomes important for engineers in designing appropriate part for turbines working at high temperatures. So far there has been no report concerning alkali attack on SiAlON ceramics in the presence of SO{sub 2} and chlorine in flue gas. The goal of this project was to investigate alkali corrosion of SiAlON-Y structural ceramics under combustion conditions in the presence of sodium derived components.
- Research Organization:
- North Dakota Univ., Grand Forks, ND (United States). Energy Research Center
- Sponsoring Organization:
- USDOE Assistant Secretary for Fossil Energy, Washington, DC (United States)
- DOE Contract Number:
- FC21-93MC30097
- OSTI ID:
- 305934
- Report Number(s):
- DOE/MC/30097-5616; ON: DE97002261; TRN: AD-a338 213
- Resource Relation:
- Other Information: PBD: 25 Feb 1997
- Country of Publication:
- United States
- Language:
- English
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