Soluble cores for composite manufacturing: process optimization through design-of-experiment method

Additive Manufacturing has advanced significantly in the latest years and is transitioning from a novel concept to an industrial scale manufacturing method. Post development of the Fused Deposition Modelling (FDM) additive manufacturing technology, filaments have been discovered that can be dissolved in a solution. This property can be utilized in combination with the rapid prototyping concept, allowing us to create models, then wrapping them in composite material and finally dissolving the model to retrieve the composite structure without any damage to it. This is the FDM Soluble Cores method, which, along with the widespread implementation of composite materials, like carbon fiber, provide a good option for prototyping. The purpose of this thesis is to verify the operating envelope of the soluble material by creating structures of different shapes and different densities and then wrapping them in laminated carbon fiber, a composite material. These models have to withstand the elevated temperature and pressure of the autoclave, which may vary per the properties of the resin or fibers. The selection of parameter adjustment for the experiments is done by an optimization referred as Design of Experiment. All successful cases with the respective selected options of the model and the autoclave are documented and compiled for future use by manufacturers and engineers, creating a table of results. This helps improve the lamination procedure of the structures and improve the resulting composites. The results of the thesis may be used to improve rapid prototyping applications on the Research & Development process of a product. The prototypes then can be quality assessed and verified, ready for mass production. The results can also be utilized in small scale, time-sensitive productions.