Effects of moisture on fatigue behavior of SiC/SiC composite at elevated temperature

✍ Scribed by Shankar Mall

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 690 KB
• Volume: 412
• Category: Article
• ISSN: 0921-5093
• DOI: 10.1016/j.msea.2005.08.040

✦ Synopsis

The effects of moisture on fatigue performance of a ceramic matrix composite (CMC) at an elevated temperature were investigated. CMC consisted of silicon carbide fiber reinforced in silicon carbide matrix with boron nitride (BN) interphase. Two series of tension-tension fatigue tests at a frequency of 10 Hz with a stress ratio of 0.1 were conducted at 750 • C: (1) under dry environment test condition (with 0% moisture content) and (2) under humid environment test condition (with 60% moisture content). Fatigue life diagrams were developed under these two conditions. Moisture decreased the fatigue life at a prescribed stress level relative to that without moisture. A detailed microscopic analysis showed that moisture caused embrittlement of the interphase between fiber and matrix, which in turn caused the degradation of fatigue performance of the tested CMC system.