Stochastic Finite Element Analysis Framework for Modelling Mechanical Properties of Particulate Modified Polymer Composites

Polymers have become indispensable in many engineering applications because of their attractive properties, including low volumetric mass density and excellent resistance to corrosion. However, polymers typically lack in mechanical, thermal, and electrical properties that may be required for certain engineering applications. Therefore, researchers have been seeking to improve properties by modifying polymers with particulate fillers. In the research presented herein, a numerical modeling framework was employed that is capable of predicting the properties of binary or higher order composites with randomly distributed fillers in a polymer matrix. Specifically, mechanical properties, i.e., elastic modulus, Poisson’s ratio, and thermal expansion coefficient, were herein explored for the case of size-distributed spherical filler particles. The modeling framework, employing stochastic finite element analysis, reduces efforts for assessing material properties compared to experimental work, while increasing the level of accuracy compared to other available approaches, such as analytical methods. Results from the modeling framework are presented and contrasted with findings from experimental works available in the technical literature. Numerical predictions agree well with the non-linear trends observed in the experiments, i.e., elastic modulus predictions are within the experimental data scatter, while numerical data deviate from experimental Poisson’s ratio data for filler volume fractions greater than 0.15. The latter may be the result of morphology changes in specimens at higher filler volume fractions that do not comply with modelling assumptions.

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Stochastic Finite Element Analysis Framework for Modelling Electrical Properties of Particle-Modified Polymer Composites

Nanomaterials ◽

10.3390/nano10091754 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1754

Author(s):

Hamidreza Ahmadi Moghaddam ◽

Pierre Mertiny

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Electrical Properties ◽

Spherical Particles ◽

Effect Of Temperature ◽

Filler Materials ◽

Stochastic Finite Element ◽

Modeling Framework ◽

Element Analysis ◽

Stochastic Finite Element Analysis

Properties such as low specific gravity and cost make polymers attractive for many engineering applications, yet their mechanical, thermal, and electrical properties are typically inferior compared to other engineering materials. Material designers have been seeking to improve polymer properties, which may be achieved by adding suitable particulate fillers. However, the design process is challenging due to countless permutations of available filler materials, different morphologies, filler loadings and fabrication routes. Designing materials solely through experimentation is ineffective given the considerable time and cost associated with such campaigns. Analytical models, on the other hand, typically lack detail, accuracy and versatility. Increasingly powerful numerical techniques are a promising route to alleviate these shortcomings. A stochastic finite element analysis method for predicting the properties of filler-modified polymers is herein presented with a focus on electrical properties, i.e., conductivity, percolation, and piezoresistivity behavior of composites with randomly distributed and dispersed filler particles. The effect of temperature was also explored. While the modeling framework enables prediction of the properties for a variety of filler morphologies, the present study considers spherical particles for the case of nano-silver modified epoxy polymer. Predicted properties were contrasted with data available in the technical literature to demonstrate the viability of the developed modeling approach.

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The equivalent method of double V-wing honeycombs on the in-plane dynamic impact

Journal of Reinforced Plastics and Composites ◽

10.1177/0731684421990867 ◽

2021 ◽

pp. 073168442199086

Author(s):

Yunfei Qu ◽

Dian Wang ◽

Hongye Zhang

Keyword(s):

Mechanical Properties ◽

Finite Element Analysis ◽

Finite Element ◽

Elastic Modulus ◽

Energy Absorption ◽

Width Ratio ◽

Size Factor ◽

Dynamic Impact ◽

Element Analysis ◽

Equivalent Method

The double V-wing honeycomb can be applied in many fields because of its lower mass and higher performance. In this study, the volume, in-plane elastic modulus and unit cell area of the double V-wing honeycomb were analytically derived, which became parts of the theoretical basis of the novel equivalent method. Based on mass, plateau load, in-plane elastic modulus, compression strain and energy absorption of the double V-wing honeycomb, a novel equivalent method mapping relationship between the thickness–width ratio and the basic parameters was established. The various size factor of the equivalent honeycomb model was denoted as n and constructed by the explicit finite element analysis method. The mechanical properties and energy absorption performance for equivalent honeycombs were investigated and compared with hexagonal honeycombs under dynamic impact. Numerical results showed a well coincidence for each honeycomb under dynamic impact before 0.009 s. Honeycombs with the same thickness–width ratio had similar mechanical properties and energy absorption characteristics. The equivalent method was verified by theoretical analysis, finite element analysis and experimental testing. Equivalent honeycombs exceeded the initial honeycomb in performance efficiency. Improvement of performance and weight loss reached 173.9% and 13.3% to the initial honeycomb. The double V-wing honeycomb possessed stronger impact resistance and better load-bearing capacity than the hexagonal honeycomb under impact in this study. The equivalent method could be applied to select the optimum honeycomb based on requirements and improve the efficiency of the double V-wing honeycomb.

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