| Autor: |
R. E. Tressler, John R. Hellmann, A. E. Segall |
| Rok vydání: |
1994 |
| Předmět: |
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| DOI: |
10.1016/b978-0-08-042133-9.50026-5 |
| Popis: |
A comprehensive thermal shock and fatigue methodology was developed for ceramics used in indirect heating and heat-exchanger applications. The methodology employed a narrow circumferential helium quench to thermally shock and fatigue three commercially available silicon carbide tubes from 1000 0 C Detailed transient temperature measurements required for thermal and stress calculations were obtained through the use of micro-thermocouples positioned along the internal surface of the tubes. Acoustic emissions were used for in situ monitoring of crack initiation and propagation of the resident flaw populations during single and repeated (up to 10) thermal shocks. Destructive burst tests were then used to correlate the existence, extent, and statistical (Weibull) nature of the damage induced by the cycling. Results indicated a vulnerability of all three materials to thermal shock damage with evidence of fatigue mechanisms also at work. In any case, the complex stress distributions computed from an FEA-based inverse heat transfer analysis were required to understand the observed damage and apparent fatigue behavior. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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