An intelligent experimental approach for the optimization of the process parameters for the thermoforming of plastics and composites (doctoraatsonderzoek Bart Van Mieghem)

Despite the existence of commercial simulation software, the thermoforming process on an industrial scale is a primarily experience and trial & error based technology, resulting in suboptimal processes. This has many causes:

• The software is expensive;
• The software does not take into account all thermal and physical aspects of this complex process;
• A process that takes into account all these aspects would inevitably require a large set of input data and unreasonable computational power;
• The heating / cooling of blanks and tools is not uniform and homogenous, adding to the process complexity;
• Variation of process parameters jeopardizes the process robustness and requires higher safety margins and blank thicknesses;

• Lack of time in the start-up of the production limits the number of experiments in the trial & error approach.

The goal of this doctorate research is to develop a methodology to optimize the process parameters for thermoforming by means of intelligent experimentation.

The first phase focuses on standard commercial thermoformable plastics, that will be used to study the temperature distribution during heating, blank transfer and thermoforming, and its effect on the formability and thickness distribution of the formed part, including a sensitivity analysis of the process parameters on the part thickness.

This experience will be used in a second phase to define the necessary and logical steps for an experimental optimization of the process parameters, resulting in a robust process with minimized material use.

In the final phase of the doctorate, the knowledge base will be extended towards short and long fiber thermoplastic composites.