TY - JOUR
T1 - Shear characterisation of uni-directional fibre reinforced thermoplastic melts by means of torsion
AU - Haanappel, Sebastiaan
AU - Akkerman, Remko
PY - 2014
Y1 - 2014
N2 - Intra-ply shear appears during the forming process of hot thermoplastic laminates with a uni-directional fibre reinforcement. This paper proposes a torsion bar test to characterise the longitudinal shear mechanism, which can be performed with a standard rheometer. Sensitivity analyses showed that most reliable shear property measurements can be obtained by using torsion bar specimens with a close to square cross section. The method is implemented in practise and critically evaluated. Storage and loss moduli were determined for carbon UD/PEEK specimens at high temperatures. Non-linear material behaviour was found for relatively small shear strains. The linear regime was focussed on subsequently, where the characteristics were found to be similar to that of a visco-elastic solid or weak gel, confirmed by a dominant storage modulus and a weak frequency dependency. Future work is recommended to be focussed on the large strain regime, for which this paper provides a found basis
AB - Intra-ply shear appears during the forming process of hot thermoplastic laminates with a uni-directional fibre reinforcement. This paper proposes a torsion bar test to characterise the longitudinal shear mechanism, which can be performed with a standard rheometer. Sensitivity analyses showed that most reliable shear property measurements can be obtained by using torsion bar specimens with a close to square cross section. The method is implemented in practise and critically evaluated. Storage and loss moduli were determined for carbon UD/PEEK specimens at high temperatures. Non-linear material behaviour was found for relatively small shear strains. The linear regime was focussed on subsequently, where the characteristics were found to be similar to that of a visco-elastic solid or weak gel, confirmed by a dominant storage modulus and a weak frequency dependency. Future work is recommended to be focussed on the large strain regime, for which this paper provides a found basis
KW - IR-89259
KW - METIS-302166
U2 - 10.1016/j.compositesa.2013.09.007
DO - 10.1016/j.compositesa.2013.09.007
M3 - Article
VL - 56
SP - 8
EP - 26
JO - Composites Part A: Applied Science and Manufacturing
JF - Composites Part A: Applied Science and Manufacturing
SN - 1359-835X
ER -