A Comparison of Experimental and Computation Results of Finding Effective Characteristics of Elastic Properties of Polymer Layered Composites from Carbon and Glass Fabrics

Abstract

Anisotropy of mechanical properties of the entire material and each of its layers is characteristic for polymer layered composite materials, as well as the fact that production processes of the composite material and parts from it are often combined in time. In this case, the elastic properties and strength of the material will be different not only in the thickness of the part, but also at each point. All this leads to a complication of the design process, which is due to the need to determine the elastic properties and strength of the polymer layered composite materials, taking into account the structure of the entire material and each of its layers. This work aims at evaluating the existing computational methods of finding effective characteristics of elastic properties by comparing computation results obtained by various methods with each other, as well as with the experimental results related to elastic properties of polymer layered composite materials from carbon and glass fabrics. We estimated the computational methods of finding effective characteristics of the elastic properties of composites based on the experimental results of finding the characteristics of the elastic properties of polymer layered composite materials made of carbon and glass fabrics, differing in density and type of weaving. The experimental values of the effective characteristics of elastic properties were determined as a result of standard tensile tests of laboratory specimens. As a result of the study, it was found that all the considered models and methods give consistent results when calculating the longitudinal modulus of elasticity E 11, the results of calculating shear modulus E 33 and shear moduli G 12 and G 23 are less consistent for all the considered materials. The comparison of the results of the experimental studies and computations showed that the Chamis model and the bridge model are better than other models to predict the values of the longitudinal elastic modulus.

Constructing a two-level computational model of cross-ply fiberglass-reinforced plastic from micromechanical testing

“…The prediction of the elastic properties of polymer composite materials depending on the volume fraction of reinforcing particles is based on analytical and computational micromechanical models. 9,10 Analytical models can be divided into five groups 9,11,12 : phenomenological, semi-empirical, elastic approximation, homogenization, and physically based models. As was shown earlier, 9,10 analytical models of micromechanics allow us to predict elastic properties in polymer fiber composites with acceptable engineering accuracy.…”

“…9,10 Analytical models can be divided into five groups 9,11,12 : phenomenological, semi-empirical, elastic approximation, homogenization, and physically based models. As was shown earlier, 9,10 analytical models of micromechanics allow us to predict elastic properties in polymer fiber composites with acceptable engineering accuracy. The models listed above, with the exception of physically based ones, cannot be used to construct coupled multilevel models due to the impossibility of applying boundary conditions obtained from another level.…”

“…It is possible to use computational models as an alternative to physically based ones when predicting the elastic properties of a composite and its behavior at different scale levels depending on the effect on the structure. Earlier studies 9,10,[13][14][15] showed that computational models can accurately describe the behavior of composites under external thermomechanical influences. Using such models with the application of a multilevel approach to the description of the mechanical behavior of a composite material allows us to simulate its behavior at different scale levels, to identify stress concentration foci, and to determine conditions for the occurrence and development of microdefects in the material depending on the stress state type, the size and shape of the reinforcement at the micro level.…”