Transient Creep Behavior of a Plain Woven SiC Fiber/SiC Matrix Composite

The present work investigates the transient creep behavior of a plain woven Tyranno™ Lox-M (Si-Ti-C-O) fiber/SiC matrix composite at 1473K in air. Tensile creep tests were carried out under a constant load between 80 and 160MPa. A creep strain rate is generally represented by e∝ σn with a constant stress exponent, however the stress exponent decreased with time for this composite material. Monotonic tensile tests were also conducted for loading rates of 0.03, 0.3, and 3kN/min in order to investigate the effect of creep strain on tensile stress/strain behavior. Based on the empirical transient creep equation and creep-hardening model, stress/strain curves under monotonic tensile loading were predicted. A good correlation was obtained between the predicted and measured composite stress/strain curves using strain-hardening model.