Influence of test mode, test rate, specimen geometry, and bending on tensile mechanical behavior of a continuous fiber ceramic composite

ASTM Test Method for Monotonic Tensile Strength Testing of Continuous Fiber-Reinforced Advanced Ceramics with Solid Rectangular Cross-Section Specimens at Ambient Temperatures (C 1275) was used to investigate the effects of test mode (load versus displacement), test rate (fast versus slow), specimen geometry (straight-sided versus reduced-gage section), specimen volume (long/thin versus short/fat), and bending in tension for a twelve-ply, two-dimensional, plain weave SiC fiber reinforced/SiC matrix continuous fibre ceramic composite. Although it appeared that graceful failure is sometimes accentuated by displacement control at slow rates, a two-way analysis of variance (ANOVA) with replication at the 95% significance of test rate, test mode or specimen geometry for proportional limit stress. Similarly, for ultimate tensile strength there was no significance of test rate or test mode although there was a significance of specimen geometry. Finally, for this two dimensional, plain weave fiber architecture there was no significance of test rate, test mode, or specimen geometry (including straight-sided specimens) on facture location. Proportional limit stress decreased with increasing bending while ultimate tensile strength appeared independent of bending.