PSI - Issue 80

Stanislav Buklovskyi et al. / Procedia Structural Integrity 80 (2026) 146–156 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig.5. Effective thermal conductivity of CB/UHMWPE nanocomposites. Numerical predictions vs. experimental measurements.

As expected, the overall thermal conductivity of the composite increases with the increase of the concentration of conductive CB inclusions. The highest discrepancy observed for 1 wt % and 10 wt % CB/UHMWPE nanocomposites. The 1 wt % data point exhibits a spike most likely related to inconsistencies in the specimen preparation. At 10 wt % of CB, the continuity of the overall material is probably violated due to high concentration of CB (and potential presents of micro voids) in the CB-containing layers.

5. Conclusions This study investigates the effective thermal conductivity of CB/UHMWPE nanocomposites utilizing mesoscale finite element models based on X-ray micro-computed tomography. The modeling approach accounts for the complex material microstructure by introducing homogenized CB- containing layers observed on μCT scans. The properties of the layers were estimated utilizing the analytical Mori-Tanaka approach for thermal conductivity. This numerical framework can be generalized and extended to other composite systems with comparable inclusion morphology and spatial distribution. The key findings are summarized below: • Microstructural characterization via μCT shows a heterogeneous composite structure composed of UHMWPE granules encapsulated by CB-containing intergranular layers. For CB weight fractions ranging from 0 – 10%, the volume fraction of these layers reaches up to 11.2%, with local CB concentrations within the layers approaching 50%. • The proposed numerical approach integrates μCT -based statistical analysis of UHMWPE granule geometry with the observed CB-containing layers to construct synthetic mesoscale RVEs. This methodology, detailed in Section 3.1, allows microstructural representation in finite element models. • Micromechanical modeling enables the estimation of the effective thermal conductivity of the CB-containing layers. Based on the experimentally measured thermal conductivity values for bulk UHMWPE, the effective thermal conductivity of layers was found to range between approximately 0.4 and 1.08 / . • The effective thermal conductivities extracted from the mesoscale FEA modeling of RVEs confirmed the hypothesis of the overall thermal isotropy of the considered CB/UHMWPE nanocomposites.