Due to their tremendous mechanical properties and manufacturability, long fiber thermoplastic composites offer many advantages for light-weighting materials. Their local elastic properties are determined as a function of fiber length and fiber orientation. Thus, for use in predictive models, it is necessary to capture the fiber length distribution (FLD) and fiber orientation distribution (FOD) during injection modeling of a component. Professor Tucker of the University of Illinois has had a major impact in engineering practice as his model of FOD is used in commercial software. To date, quantifiable predictions of FLD has not received as much attention as FOD.
Prof. Tucker's group has created a novel model for fiber length attrition in a flowing fiber suspension. The model tracks the FLD during a mold flow, which evolves as the fibers buckle due to hydrodynamic forces. Our contribution to this project included implementing a reduced order model to predict FLD and implementing the result in an injection modeling simulation.
Further, the Sangid group has developed automatted tools to characterize the fiber length and orientation distributions within long fiber composites. These analyses include a complete look at the biases associated with these characterization techniques and the uncertainy propagations to final composite stiffness precitions.
Wang J, Nguyen BN, Mathur R, Sharma B, Sangid MD, Costa F, Jin X, Tucker CL, Fifield LS, “Fiber Orientation in Injection Molded Long Carbon Fiber Thermoplastic Composites,” For presentation at ANTEC, Injection Molding Division, Society of Plastics Engineers, Orlando, March 23-25, 2015.
Tucker III CL, JH Phelps, A El-Rahman, V Kunc and BJ Frame (2010). “Modeling Fiber Length Attrition in Molded Long-Fiber Composites,” Polymer Processing Society 26th Annual Meeting. Banff, Canada.