Research And Simulation Of Short Fibre Orientation In Compression Molding Of SMC

As an important process of fibre-reinforced composites, sheet molding compound (SMC) technology draws worldwide attention recently. The orientation of the reinforcing fibres changes during the deformation process, and when the matrix solidifies the final orientation pattern is retained in the part. This orientation plays a key role in determining the mechanical and physical properties of the finished product. Therefore, it is very important to have some insight into the change of fibre orientation during flow.At first the rheology behavior of SMC is analyzed and a Generalized Hele-Shaw model (GHS), based on the theory of fluid mechanics, is adopted as theory model of compression molding. Then theories of describing and predicting fibre orientation in flowing suspensions are investigated and a mathematics model of planar orientation in a two-dimensional domain is derived. In the numerical methods section, a finite element/control volume mold filling simulation, a tensor representation of fibre orientation and a finite element solution of the transient fibre orientation equations are combined in the program. The input data and output results are visualized by means of finite element software. Finally the orientation states of 2-D thin plate are simulated in a certain velocity. The numerical results will be of a certain theoretical function to placement of SMC charge, design of mold and optimization of the technological parameters.