Investigation of the viscoelastic behavior in the hot press-forming process of uncured prepreg laminates

doi:10.19936/j.cnki.2096-8000.20221228.031

Abstract

Abstract: In the pre-forming process of uncured prepreg laminates with hot press, pressure is an important parameter that affects the performance and quality of the final product. In this study, the compression and relaxation viscoelastic behaviors of uncured prepreg laminates were investigated in different fiber orientation, displacements, velocities, and thicknesses. The results show that the power law model could accurately describe the compression behaviors of prepreg. The generalized Maxwell viscoelastic model and the fractional viscoelastic model could describe the relaxation behaviors of prepreg, respectively. The theoretical fitting curves match very well with experimental data at each condition and the R-squared value is greater than 0.96. Compared with the generalized Maxwell model, the fractional viscoelastic model requires fewer parameters and has more definite physical significance, which is more suitable for describing the viscoelastic deformation behaviors of prepreg in the process of hot press-forming.

Key words: viscoelastic behavior, stress relaxation, the fractional viscoelastic model, uncured prepreg laminates, hot press-forming, composites

CLC Number:

TB332

LI Zhefu, LIU Weiping, SUN Baozhong, YUE Guangquan, TAN Yuan, ZHANG Jian. Investigation of the viscoelastic behavior in the hot press-forming process of uncured prepreg laminates[J]. COMPOSITES SCIENCE AND ENGINEERING, 2023, 0(2): 84-93.

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