Combustion Rig Durability Testing of Turbine Ceramics
A necessary prerequisite to accurate prediction of component life and achievement of system reliability is an understanding of the oxidation/corrosion mechanisms and kinetics for ceramic gas turbine components. In many ways, the situation is analogous to metals technology. The mechanism and rate of oxidation/corrosion can vary markedly, depending upon the composition of the environment, the temperature, and the composition and structure of the material. However, the mode of failure is different for ceramics than for metals. Metals are life-limited in oxidation and corrosion by material removal and the resulting loss in performance. The material-removal rate is much slower for ceramic materials, but the life appears to be limited by formation of surface flaws that reduce the effective material strength.
KeywordsSpecimen Holder Flexure Strength FlOW CONTROl VAlVE Cyclic Exposure Spring Washer
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- 1.D. W. Richerson and T. M. Yonushonis, “Environmental Effects on the Strength of Silicon Nitride Materials,” in: Proceedings of the 1977 DARPA/NAVSEA Ceramic Gas Turbine Demonstration Engine Program Review, MCIC-78-36, 247–271 (1978).Google Scholar
- 2.C. Larsen and G. C. Walther, “Property Screening and Evaluation of Ceramic Turbine Engine Materials,” AFML Contract F33615-75-C-5196, Interim Technical Report No. 5 (1978).Google Scholar