In this paper, we investigate ultra-high-molecular-weight-polyethylene (UHMWPE) doped with conductive carbon black (CCB) nanoparticles. This nanocomposite is considered a candidate for biomedical applications such as orthopedics. Micro-computed tomography (μCT) and scanning electron microscopy studies show that the composite has a complex microstructure consisting of larger particles of UHMWPE surrounded by a thin layer containing a high concentration of CCB nano inclusions. The overall mechanical properties of these composites depend on the volume fraction of CCB and the manufacturing procedures e.g., compression molding or equal channel angular extrusion. To predict the effective elastic properties of the CCB/UHMWPE nanocomposite, we propose a multiscale modeling framework based on a combined analytical-numerical approach. μCT images are processed to extract the size, shape, and orientation distributions of UHMWPE particles as well as the volume fractions and spatial distribution of CCB containing layer. These distributions are used to develop multiscale numerical models of the composite including finite element analysis of representative volume elements on the mesoscale, and micromechanical predictions of CCB containing layer on the microscale. The predictive ability of the models is confirmed by comparison with the experimental measurements obtained by dynamic mechanical analysis.
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Effect of Unit Cell Geometry and Fiber Waviness on the Overall Mechanical Response of 3D Woven Composites
Effects of two meso-scale geometry generation approaches on finite element predictions effective elastic properties of an orthogonal 3D woven composite are studied in this paper. In particular, one model is created by simulating the weaving process in the software DFMA (Kansas State University). The second model is created by directly processing X-ray microtomography (μCT) data. Experimental measurements of transverse Young’s moduli are used to inform the accuracy of the predicted elastic results. In both cases, a unit cell with in-plane periodic boundary conditions is modeled, which has not been previously done in the case of μCT-based models. The effect of high frequency oscillations in tow element orientations imparted by a wavy centerline (artifact of μCT image processing) on the elastic properties is studied. The μCTbased model is then used to simulate tension-to-failure.
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- Award ID(s):
- 1662098
- NSF-PAR ID:
- 10175717
- Date Published:
- Journal Name:
- Proceedings of the 34th ASC Technical Conference, Atlanta, GA, USA, 2019
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.12783/asc34/31425
