High-fidelity simulation model for moisture-induced deformation of CFRP structure considering anisotropic nonlinear moisture absorption-desorption characteristics

• Published in: Composites. Part A, Applied science and manufacturing Applied science and manufacturing, 2023-02, Vol.165, p.107324, Article 107324
• Main Authors: Kitamoto, Kazuya, Minakuchi, Shu, Yokozeki, Tomohiro
• Format: Article
• Language: English
• Subjects: A. Polymer-matrix composites (PMCs); anisotropy; B. Environmental degradation; carbon fibers; D. Moisture; deformation; epoxides; finite element analysis; moisture diffusivity; Optical fiber sensor; optical fibers; prediction; simulation models; water content
• ISSN: 1359-835X; 1878-5840
• DOI: 10.1016/j.compositesa.2022.107324

This study developed a high-fidelity simulation model for predicting moisture-induced deformation of polymer-based composite structures. First, to identify the anisotropic moisture diffusion in unidirectional carbon fiber/epoxy composites, coupon level tests were conducted for each principal material direction (i.e., fiber-parallel, in-plane transverse, and out-of-plane transverse directions). In addition, the moisture-induced strain in the fiber and the transverse directions of unidirectional composites was evaluated using an optical fiber sensor. Nonlinear strain against moisture content was identified in each direction. Next, the strain history in the tube element for the metering truss structure was monitored using an optical fiber sensor during the moisture absorption–desorption cycle. Finally, a prediction of the strain behavior was provided using a finite element analysis (FEA) model. The model accurately reflected the complex moisture absorption–desorption characteristics (e.g., directional dependence, nonlinearity, and irreversibility) obtained from the coupon tests. The prediction was compared with the monitoring data and agreed with the experiment.