Optimization of the injection molding process for short-fiber-reinforced composites

The injection molding process of short fiber-reinforced polymer composites was investigated using smoothed particle hydrodynamics method. The polymer melt was modeled as a power law fluid, and the fibers were considered as rigid bodies. The flow behavior of short fiber-reinforced polymer composite melt and the motion and orientation of fibers were studied. The results showed that U-shaped fountain flow was generated at the flow front, and the center of the flow front gradually sank during the injection molding process; fibers were aligned to the flow direction in the cavity and near the wall in the sprue, and fibers accumulated at some points in the cavity. Additionally, the initial fiber configuration in the model influenced the final fiber orientation slightly. It was also found that the fiber orientation factor increased with the increase of fiber aspect ratio, and decreased with the increase of fiber content.

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Double Scale Coupling Model of Plastic Injection Molding

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.472-475.2148 ◽

2012 ◽

Vol 472-475 ◽

pp. 2148-2151 ◽

Cited By ~ 1

Author(s):

Lin Jian Shang Guan ◽

Yang Yang ◽

Jie Yang

Keyword(s):

Injection Molding ◽

Short Fiber ◽

Scale Model ◽

Small Scale ◽

Injection Molding Process ◽

Fiber Reinforced ◽

Scale Problem ◽

Molding Process ◽

Multi Scale ◽

Double Scale

The process of short fiber reinforced injection molding is a typical multi-scale problem, it has become a cutting-edge issue of the field of polymer molding to study clearly the mesoscopic structure changing rules in the whole molding processing. Aiming at the processing of glass fiber reinforced polypropylene injection, basing on the foundation of macro continuum medium model, approximated short fiber reinforced injection molding process as macro-mesoscopic double scale problem composed by macro-flow and small-scale short fiber movement, establish the double scale model, which couple Mesoscopic fiber orientation. And the cooling crystallization model was established by learning from multi-scale simulation of liquid metal crystallization method.

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A computational modeling approach based on random fields for short fiber-reinforced composites with experimental verification by nanoindentation and tensile tests

Computational Mechanics ◽

10.1007/s00466-020-01958-3 ◽

2021 ◽

Author(s):

Natalie Rauter

Keyword(s):

Numerical Simulations ◽

Correlation Functions ◽

Material Properties ◽

Random Fields ◽

Tensile Tests ◽

Short Fiber ◽

Fiber Reinforced Composites ◽

Reinforced Composites ◽

Fiber Reinforced ◽

Component Level

AbstractIn this study a modeling approach for short fiber-reinforced composites is presented which allows one to consider information from the microstructure of the compound while modeling on the component level. The proposed technique is based on the determination of correlation functions by the moving window method. Using these correlation functions random fields are generated by the Karhunen–Loève expansion. Linear elastic numerical simulations are conducted on the mesoscale and component level based on the probabilistic characteristics of the microstructure derived from a two-dimensional micrograph. The experimental validation by nanoindentation on the mesoscale shows good conformity with the numerical simulations. For the numerical modeling on the component level the comparison of experimentally obtained Young’s modulus by tensile tests with numerical simulations indicate that the presented approach requires three-dimensional information of the probabilistic characteristics of the microstructure. Using this information not only the overall material properties are approximated sufficiently, but also the local distribution of the material properties shows the same trend as the results of conducted tensile tests.

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Anisotropic Effective Moduli of Cracked Short-Fiber Reinforced Composites

Journal of Applied Mechanics ◽

10.1115/1.2791629 ◽

1999 ◽

Vol 66 (3) ◽

pp. 709-713 ◽

Cited By ~ 5

Author(s):

R. S. Feltman ◽

M. H. Santare

Keyword(s):

Short Fiber ◽

Fiber Reinforced Composites ◽

Reinforced Composites ◽

Effective Moduli ◽

Fiber Reinforced ◽

Fiber Fracture ◽

Composite Systems ◽

Reinforced Composite ◽

Anisotropic Elastic ◽

Energy Dissipated

A model is presented to analyze the effect of fiber fracture on the anisotropic elastic properties of short-fiber reinforced composite materials. The effective moduli of the material are modeled using a self-consistent scheme which includes the calculated energy dissipated through the opening of a crack in an arbitrarily oriented elliptical inclusion. The model is an extension of previous works which have modeled isotropic properties of short-fiber reinforced composites with fiber breakage and anisotropic properties of monolithic materials with microcracks. Two-dimensional planar composite systems are considered. The model allows for the calculation of moduli under varying degrees of fiber alignment and damage orientation. In the results, both aligned fiber systems and randomly oriented fiber systems with damage-induced anisotropy are examined.

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Multiscale thermomechanical modeling of short fiber-reinforced composites

Science and Engineering of Composite Materials ◽

10.1515/secm-2015-0487 ◽

2017 ◽

Vol 24 (5) ◽

pp. 765-772 ◽

Cited By ~ 1

Author(s):

Dawei Jia ◽

Huiji Shi ◽

Lei Cheng

Keyword(s):

Thermal Loading ◽

Volume Fraction ◽

Numerical Procedure ◽

Thermal Conditions ◽

Cyclic Hardening ◽

Short Fiber ◽

Fiber Reinforced Composites ◽

Reinforced Composites ◽

Fiber Reinforced ◽

Thermomechanical Modeling

AbstractA study of the micromechanical behavior to predict the overall response of short fiber-reinforced composites under cyclic mechanical and thermal loading is presented. The instantaneous average over a “representative volume” of the material is considered. The influence of the short fiber’s aspect ratio, volume fraction, and spatial orientation has been investigated. The linear combined hardening model is used to describe the cyclic hardening effects in the case of metal matrix. A numerical procedure is used to predict the response of composites under mechanical and thermal conditions. The results of the numerical procedure have been compared to the results of three different models and to published experimental data.

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