Fatigue behavior of Nextel (TM) 312/Blackglas (TM) ceramic matrix composite with tensile and zero mean load

This study characterized a woven fabric reinforced ceramic matrix composite , Nextel(TM) 312/Blackglas(TM), under monotonic and fatigue loading conditi ons at room and elevated (760 degreesC) temperatures in order: (1) to inves tigate monotonic tensile and compressive loading behavior at room and eleva ted temperatures, (2) to establish the fatigue life diagrams (S-N curves) w ith tensile and zero mean load under low frequency (0.1 Hz) cycling conditi on at room and elevated temperatures, and (3) to investigate damage mechani sms and failure modes under monotonic and fatigue loading conditions. Fatig ue lives under tension-compression cycling were much longer than those unde r tension-tension cycling at a given stress range for both room and elevate d temperatures. However, fatigue lives under tension-compression cycling we re much shorter than those under tension-tension cycling for a given maximu m stress level at room temperature, but lives were about equal under these two loading conditions for a given maximum stress level at elevated tempera tures. Further, fatigue lives were much shorter at elevated temperature tha n their counterparts at room temperature for a given stress range or for a given maximum stress level under the both tension-tension and tension-compr ession cycling conditions.