Process Modeling in Structural Composites Molding

The multiplicity of composite manufacturing technologies and materials opens up a wide range of possibilities for designers, but at the same time complicates the task of selecting and fine-tuning manufacturing processes. The choice of a technology is a technical and economic challenge, and must be based on the type and number of parts to be produced, the production rate, the investments to be made, etc. There are in fact many criteria to be taken into account, making the selection of the right process a tricky one. What's more, the physical and chemical phenomena involved in molding advanced composites are complex and, what's more, coupled, adding a further degree of complexity [AM 3 718] . Once the choice of technology has been made, manufacturing parameters need to be optimized. Repeated tests on prototypes help to specify the value of these parameters and determine the best strategy. This solution takes a long time to implement and to bring to fruition, but it also has the disadvantage of being costly, since a change in one of the elements of the specifications may call into question the initial choices.

Faced with increasingly complex applications and shorter development times, empiricism must give way to methods based on a deeper understanding of the links between process control parameters and the properties of the materials used. In this context, computational tools describing composite manufacturing in relation to part design are becoming necessary tools in the design-manufacturing chain, and are helping to develop and deploy composite technologies and solutions in the industrial world.

The aim of this article is to apply some of the models presented in [AM 3 718] to situations encountered in structural composite molding processes, and which are of practical interest for estimating quantities such as resin pressures, temperatures and characteristic times.

Structural composites are thermoplastic or thermosetting polymers reinforced with continuous fibers. Molding covers technologies where polymer flows play an essential role in part manufacture.