Micromechanics-based progressive damage models for prediction of effective mechanical behavior of particulate- and fiber-reinforced composites

Abstract

This dissertation presents the micromechanics-based analytical models for simulating the effective mechanical behavior of particulated- and fiber-reinforced composites. In a micromechanics-based analysis, the composite materials are simplified in characterization models based on a widely accepted homogenization theory. The ensemble-volume average method based on homogenization theory is used for predicting the effective behavior of particulated- and fiber-reinforced composites in this work. In particular, the progressive damage induced by interface debonding and void evolution is considered to describe the damage characteristic in the composites. This dissertation can be divided into five works as follows: 1) Elastic-damage modeling for particulate composites considering cumulative damage, 2) Modeling of particle debonding and void evolution in particulated ductile composites, 3) An RVE-based micromechanical analysis of fiber-reinforced composites considering fiber size dependency, 4) Elastoplastic modeling of circular fiber-reinforced ductile matrix composites considering a finite RVE, and 5) Closed form solution of the exterior-point Eshelby tensor for an elliptical cylindrical inclusion. This thesis includes the expansion of the analytical approach, verification results of the proposed models, implementation of a variety of parametric study, and comparison between the analytical predictions and experimental results. The proposed micromechanics-based analytical models are validated through comparison with correlation studies on the analytical and experimental results. The use of the proposed models makes it possible to accurately simulate the progressive damage behaviors of the particulate- and fiber-reinforced composites. In addition, the proposed model with further researches will contribute to efficiently predict the damage behavior of composite materials in the range from nanoscale to microscale.