The Effect of Micromechanics Models, 2D and 3D Numerical Modeling for Predicting Mechanical Properties of PP/Alfa Short Fiber Composites

In the present work, we propose to confront two modeling techniques for predicting the macroscopic properties of short alfa fiber-reinforced polypropylene composites. The first modeling is a micromechanical analysis using Mori-Tanaka, Self-coherent, Diluted, Voigt, Reuss, and Neerfeld-hill models. The second modeling is digital using a specific finite element technique called the “Projected fiber Approach (FP)”. In the framework of this study, both 2D and 3D finite element analysis, based on the Projected fiber Approach (FP), were used. First, we proposed an inverse approach using these analytical and finite element models to predict Young’s modulus of alfa fiber. Then, we compared the results obtained with the experiment values in the literature. This comparison showed that the micromechanical models underestimated the alfa fiber Young’s modulus, while the finite element approach FP allowed good framing of the experimental values. Moreover, we investigated the effect of fiber content on the predicted elastic properties of polypropylene matrix reinforced with randomly distributed short alfa fibers. We noticed that the Mori-Tanka model is more accurate than the self-consistent method. The FP approach's estimations were close to the experimental values. For example, Young's modulus for the PP/Alfa with 30 wt% fiber content was underestimated with an error of 4.3%. It is shown that the 2D FP approach can provide calculated results with sufficient prediction accuracy.