PSI - Issue 52

Jun Koyanagi et al. / Procedia Structural Integrity 52 (2024) 187–194

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Author name / Structural Integrity Procedia 00 (2019) 000 – 000

Fig. 5 Stress-strain relationship of numerical and experimental results for the test interrupted with constant strain.

3.2 Numerical simulation for the tensile failure of randomly oriented short fiber reinforced plastics based on a viscoelastic entropy damage criterion (Kagawa et al. 2023)

Using Mori-Tanaka theory with viscoelastic entropy-based damage criterion, the tensile strengths randomly aligned short fiber reinforced composite material under various testing speeds are simulated and compared with experimental results as shown in Fig. 6. In these studies, fiber/matrix interface is assumed to be perfect bonding, but this is reasonable because most of interface show high strength s(Sato et al. 2017, Sato et al. 2018). The estimated strengths show good agreement with individual experimental results. Thus, employing entropy-damage criterion, various strengths including under cyclic loadings can be precisely obtained in micromechanical viewpoint. The results obtained in these microscale numerical simulations are transported into upper scale calculations.

Fig. 6 Simulation and experimental results for stress-strain curves