Tomography-based numerical reconstruction of fiber bundle and response of microstructural characteristics to mechanical behavior
Topic(s) : Material and Structural Behavior - Simulation & Testing
Co-authors :
Xinling SONG (FRANCE), Audrey HIVET (FRANCE), Anwar SHANWAN (FRANCE), Gilles HIVETAbstract :
The development of fiber-based composites depends on exhaustive experiments and intricate simulations, a process marked by considerable complexity. Since fabrics are multi-scale entities, composed of a multitude of yarns which, consist of innumerable fibers. Current technology is unable to accurately model fabric behavior at the microscopic scale, researchers incorporate behavior properties into mesoscopic scale behavior laws. This allows for a more macroscopic understanding of fabric behavior. To understand the overall behavior of fabrics in depth, it is necessary to study the behavior of the fiber yarn (the basic unit) under different mechanical paths. Due to the limitations of experimentation, simulation becomes an effective tool to study the behavior of fiber bundles under different stress conditions. The goal of this study is to create simulation tools to understand and model the behavior of a fiber yarn in microstructure to build a constitutive law of the yarn.
This study developed the existed microscale virtual estimator developed by Dr. Haji [1] and created indicators to analyze the microstructure of fiber bundle. This work creates numerical fiber bundle based on tomography and combines micro-compaction experiments with 40 polyester fibers (15mm length, 0.5mm diameter). The initial numerical fiber bundle geometry is extracted with MATLAB and input into ABAQUS® to simulate the mechanical load influence on the bundle fiber reorganization, as the experiments. The compaction behavior curve and the microstructure of fiber bundle of simulation and experiment are compared after each compaction step. From the compaction curves, the experimental and simulation results are approximate. From the fiber microscopic point of view: (i) The error between the experimental and simulated fiber positions accumulates as the compaction experiment proceeds. However, in the final compaction step, the error between simulation and experiment is optimistic, with mean values of 3.12% and 14.07% and standard deviations of 1.75 % and 7.89% with respect to the fiber bundle thickness (2.23 mm) and fiber diameter, respectively; (ii) Indicators such as the total number and angles of contacts between fibers, curvature, crimp and orientation of the fibers are in agreement with the trend of the compaction curve. The plunge change in curve of Compaction Press – Volume fraction can be explained by the microstructure of the fibers (fiber location) as well as by the indicators. The developed virtual numerical estimator and microstructural analysis tools reveal the relationship between fiber microstructure and compaction mechanical behavior, which provides an efficient and reliable research method for studying the internal mechanical properties of yarns.
This study developed the existed microscale virtual estimator developed by Dr. Haji [1] and created indicators to analyze the microstructure of fiber bundle. This work creates numerical fiber bundle based on tomography and combines micro-compaction experiments with 40 polyester fibers (15mm length, 0.5mm diameter). The initial numerical fiber bundle geometry is extracted with MATLAB and input into ABAQUS® to simulate the mechanical load influence on the bundle fiber reorganization, as the experiments. The compaction behavior curve and the microstructure of fiber bundle of simulation and experiment are compared after each compaction step. From the compaction curves, the experimental and simulation results are approximate. From the fiber microscopic point of view: (i) The error between the experimental and simulated fiber positions accumulates as the compaction experiment proceeds. However, in the final compaction step, the error between simulation and experiment is optimistic, with mean values of 3.12% and 14.07% and standard deviations of 1.75 % and 7.89% with respect to the fiber bundle thickness (2.23 mm) and fiber diameter, respectively; (ii) Indicators such as the total number and angles of contacts between fibers, curvature, crimp and orientation of the fibers are in agreement with the trend of the compaction curve. The plunge change in curve of Compaction Press – Volume fraction can be explained by the microstructure of the fibers (fiber location) as well as by the indicators. The developed virtual numerical estimator and microstructural analysis tools reveal the relationship between fiber microstructure and compaction mechanical behavior, which provides an efficient and reliable research method for studying the internal mechanical properties of yarns.