| A stamping process has been proposed for forming structural thermoplastic composite parts to reduce the weight of an automobile. The main focus of this thesis is to investigate the frictional behavior of the composite fabric under the influence of the blank holder, which is a major component of the stamping machine. A test fixture was built and experiments were conducted to investigate the effect of different parameters, such as the stamping rate, tool and fabric temperatures, normal pressure and fiber orientation, on the friction between the composite fabric and metal tool. It is concluded that the transitions between two different friction mechanisms induced a complex relationship, similar to the Stribeck curve, between the friction coefficient and test parameters. In order to avoid the typical ‘trial and error’ method for developing new technology, an analytical model, incorporating the Coulomb and Hydrodynamic friction models, was created to predict the friction coefficient at different conditions for future numerical simulation and process optimization. |
