It has been shown that a dramatic saving of dynamic fatigue testing time can be achieved with a proper use of preloading. In previous papers [1-3] we developed the analytical and numerical solutions of dynamic fatigue strength as a function of preloading for both Griffith (natural) and indentation-induced flaw systems. The solutions were verified by dynamic fatigue experiments conducted with soda-lime glass and alumina at room temperature [1,2] and with silicon nitride and alumina at high temperatures [3]. It should be noted that the magnitude of preloading to be applied is also dependent on the scatter of strength or Weibull modulus. Consequently, in this work, preloading experiments were carried out at elevated temperature using a hot-pressed silicon carbide (NC 203) both to further validate the developed equations and to determine the effect of preloading on Weibull modulus.
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