|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Fracture: 65 Years after the Weibull Distribution and the Williams Singularity
||A Probability Model for Stress Rupture Failure of Carbon Composites, Incorporating Weibull Fiber Strength Statistics, Local Fiber Load Sharing, and Matrix Creep
||Amy Engelbrecht-Wiggans, Leigh Phoenix
|On-Site Speaker (Planned)
For decades, modeling the strength of unidirectional continuous fiber composites has been based on Weibull fiber strength statistics within the framework of local micro-mechanical load sharing among failed and surviving fiber elements. Failure results, as load is increased, when a critical cluster forms and becomes unstable. Remarkably, the stress field around such a cluster has features reminiscent of Williams’ stress singularity. Despite the fibers having Weibull strength behavior, the composite tends to be non-Weibull and with much less strength variability than the fibers. Yet the usual size effect, in terms of overall composite volume under stress, remains a key feature. In this paper we extend this analytical framework to incorporate matrix creep around clusters of fiber breaks, which becomes a driver for time dependent stress rupture (static fatigue) failure. This type of model plays a key role in understanding catastrophic stress rupture in carbon composite overwrapped pressure vessels.
||Planned: Supplemental Proceedings volume