Study of strength and its reliability of SiC fiber bundle by experimental and Monte-Carlo simulation approach

Tensile tests and Monte-Carlo simulation on the strength and its reliability of the SiCCVD (formed by chemical vapor deposition) fiber bundle were performed. The experimental and simulation results were compared and analyzed by fiber bundle strength theories. The experimental results showed that the strength of the SiCCVD fiber bundle was decreased as the number of fibers in the bundle was increased; while in the process, Weibull shape parameter of the bundle strength was increased. The experimental results were in good agreement with the Monte-Carlo simulation. In addition, Monte-Carlo simulation was used to clarify the detailed relationship between the strength of the SiCCVD bundle and the number of fibers in the bundle and the simulation results were compared with that of Coleman theory. The comparison revealed that the strength of the SiCCVD bundle converged to the value of Coleman theory as the number of fibers in the bundle increased; at the same time, the rate of convergence was increased as Weibull shape parameter was increased. Furthermore, the relationship between the strength of the SiCCVD fiber bundle and Weibull shape parameter of the SiCCVD fiber strength was also examined. It was found that the strength of the SiCCVD fiber bundle increased as Weibull shape parameter was increased although the number of fibers in the bundle was countable. Finally, the breaking-down process and the number of broken-fibers in the bundle depended on the number of fibers the bundle and Weibull shape parameter of the SiCCVD fiber strength.

Research highlights
► The strength of SiCCVD fiber bundles decreased and converged to the value of Coleman's theory as the number of fibers in the bundles was increased.
► The strength of the bundles increased as Weibull shape parameter of fiber strength was increased.
► The fracture process depended on the number of fibers in the bundles and Weibull shape parameter of fiber strength.