Analysis of frictional behaviour of carbon dry woven reinforcement

During the preforming stage of woven reinforcement, in the first step of the RTM process, frictional phenomenon occurring at the tool/reinforcement interfaces and the reinforcement/reinforcement interfaces is one of the key parameters of the forming process. This behaviour must be correctly taken into account when modelling the process and a better understanding of the contact and friction phenomena occurring during the woven fabric preforming process is necessary for realistic simulation of the preforming process. Although some existing studies concerning friction of reinforcement have been published, the complex frictional behaviour of fabrics is still not completely clear. The experimental characterization of the frictional behaviour of a specific carbon woven reinforcement (G1151) used for aeronautical applications, is the aim of this paper, and three interfaces have been studied (G1151/G1151, G1151/Plexiglas, G1151/Aluminium). The Coulomb coefficients of friction occurring during contact between two layers of fabric and between the fabric and other materials have been determined. The effect of the variation of the normal pressure and the temperature on the frictional behaviour of this reinforcement has also been analysed. Comparisons between several frictional models, described in the literature, are also conducted, associated with these experimental results. This study highlights a significant tribological anisotropy of the G1151 reinforcement and a dependence of the frictional characteristics on the applied pressure and the temperatureThis work has been undertaken within the framework of the Défi composite project. The authors would like to thank Oséo for its financial support, the project leader Airbus-France and other partners (EADS IW and LoireTech) for the facilities provided