Friction Measurement on Dry Fabric for Forming Simulation of Composite Reinforcement

Abstract

Forming processes are highly influenced by all the interface conditions between the tooling and the workpieces. For thermo-mechanical processes like hot forging or cutting processes friction is widely studied for a long time but for composite parts, it is not the case because the problem is not so crucial: forming forces are generally weak enough to allow the part be realized with any forming device; surface quality is not highly affected by the friction conditions; for pre-impregnated fabrics, the viscous or even fluid matrix acts like a lubricant and avoids defects due to sticking between fibre reinforcement and metallic tools. Nevertheless, friction seems to have an important role when precise simulations are expected. Up to now, few studies have been focussed on friction during composite forming processes. The aim of the present study is to make a contribution on that topic for an experimental point of view using an high precision device able to measure small friction forces. The relative fibre orientations can be monitored in order to explore the whole range of geometrical configurations. The final goal is to develop an efficient tool for finite element simulations of dry and pre-impregnated fibre fabrics accounting for the main specificity of fabrics, that is to say their strong anisotropy.