Numerical study of distribution and orientation of fibers during the injection of thermoplastic composites

Abstract

We present in this paper a numerical simulation of the filling stage of injection molding process of thermoplastic composite reinforced with short fibers. We focused on analyzing the distribution of fiber's orientation given by the variation of values of second-order orientation's tensor in a rectangular geometry. The originality of our work is the introduction of a thermo-dependent law describing the behavior of material. This law is obtained experimentally using rheological measurements on online rheometer.

Influence of injection molding on the flexural strength and surface quality of long glass fiber-reinforced polyamide 6.6 composites

“…12, taking into account the difference between the widths of the central valley of the two orientation curves. The influence of injection speed in the fiber orientation, particularly in the core width, is documented in the literature [36]. This is explained because at low injection rates, the area of skin layer (shell) affected by the fountain effect is large than when using higher injection speeds.…”

Assessment of the Compressive Mechanical Behaviour of Injection Molded E-Glass/Polypropylene by Mechanical Testing and X-Ray Computed Tomography

“…The concept of the existence of various layers through-the-thickness with different ber preferential orientation was adopted also by Bay and Tucker [15]. The same concept alongside with modi ed rule of mixture was present in the works of Patcharaphun and Menning [16] and Miles and Rostami [17] while the effect of a potential ber alignment towards the injection ow direction on the shear properties was presented in [18] and a numerical approach/study for assessing the reinforcement characteristics can be found in [19]. The most interesting modi cation though is the addition of the parameters related to the characteristics of the reinforcing constituent such as the ber critical length and distribution to the rule of mixtures.…”

Modelling transport and deposition of non-spherical micro- and nano-particles in composites manufacturing

“…9 In this context, the understanding of the mechanisms governing nano-particle distribution and orientation is crucial not only to optimise the functionality 10 but also to avoid problems during the manufacturing such as clogging and uneven flow. Experiments have shown that the initial degree of dispersion of carbon nano-fibres matters, 11 and it is obvious that the orientation of fibres during processing of composites in general is of importance as well, as has been determined by the studies of injection moulding in general, 12,13 during shear flow 14,15 and for composites with copper fibres. 16 Most of the fabrics used during liquid moulding of structural composites have dual-scale porosity, <10 mm for pores within fibre bundles and >100 mm for the space between the bundles.…”