Title: Characterization of the Transverse Shear Viscosity of Unidirectional C/LM-PAEK

Authors: Gerben Bieleman, Wouter Grouve, Francesco Rondina, Edwin Klompen, Remko Akkerman

DOI:

Abstract: Accurate process simulations for the consolidation and forming of unidirectional (UD) thermoplastic composites require reliable descriptions of transverse flow behavior. This work presents a methodology to characterize the transverse shear viscosity of UD carbon fiber reinforced low-melting poly(aryl ether ketone) (C/LM-PAEK) using squeeze flow experiments combined with digital image correlation (DIC). Building on prior flow visualization studies, transverse squeeze flow is treated as a combination of elongational and shear deformation. The present study focuses on isolating the transverse shear component by introducing a thin PEEK polymer interlayer to control boundary conditions and enable reconstruction of local boundary shear stresses. The approach combines independent rheological characterization of the polymer interlayer, DIC-based measurement of velocity fields during squeeze flow, analytical determination of boundary shear rates, and local fitting of a power-law viscosity model. The methodology is demonstrated at a single temperature and compression rate, showing that a consistent transverse shear viscosity description can be obtained from boundary data. The proposed approach provides a foundation for future characterization over a wider range of processing conditions and will yield improved process simulation accuracy.

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Conference: SAMPE 2026

Publication Date: 2026/04/27

SKU: 16

Pages: 13

Price: $26.00