On The Anisotropic Plastic Behaviour Of Short Fibre Reinforced Thermoplastics And Its Description By Phenomenological Material Modelling

On the anisotropic plastic behaviour of short fibre reinforced thermoplastics and its description by phenomenological material modelling

A requirement for the safe design of thermoplastic parts is the ability to precisely predict mechanical behaviour by finite element simulations. Typical examples include the engineering of relevant components in automotive applications. For this purpose adequate material models are essential. In this context, the present work introduces a material modelling approach for short fibre reinforced thermoplastics (SFRTPs). SFRTP parts are processed cost-effectively by injection moulding and show a varying degree of anisotropy due to the locally inhomogeneous fibre distributions that arise during the moulding process. The presented material model considers linear-elastic behaviour and non-linear orthotropic stress-state dependent viscoplastic deformation for arbitrary fibre distributions. The constitutive equations are verified with the experiments of a PPGF30 material regarding different stress-states and orientations.

International aerospace abstracts

Fiber-dependent injection molding simulation of discontinuous reinforced polymers

This work presents novel simulation techniques for injection molding of fiber reinforced polymers. These include approaches for anisotropic flow modeling, hydrodynamic forces from fluid on fibers, contact forces between fibers, a novel fiber breakage modeling approach and anisotropic warpage analysis. Due to the coupling of fiber breakage and anisotropic flow modeling, the fiber breakage directly influences the modeled cavity pressure, which is validated with experimental data.