Simulation tools for the pre-heating, press forming and post-cooling analysis of pre-consolidated CFRTP sheets have been developed and industrially validated. The key capabilities of the software include:
Pre-heating analysis: This covers the heating prediction for the project materials using infra-red, conduction and convection heating. Numerous validation studies have shown the software to be accurate and reliable. Additional work beyond the planned project activities has included algorithms to predict temperature loss during the transfer phase between heating and press forming.
Forming analysis: More than ten studies of varying complexity have given a good basis for validation of the techniques and forming software. Phenomena such as fabric wrinkling, temperature and pressure evolvement, and the process window have been validated against test results.
Post-forming analysis: The techniques needed to predict dimensional stability have been proven. Further work will be needed to validate these for more complex parts in which 'locked-in' fibre stress created during the forming play an important role in the post-forming residual deformations and stresses.
The project has been brought to a successful conclusion and with all of the main technical objectives having been achieved. The software tools have proved to predict well the different phases of the forming process and are a promising means to design and optimise both the part and manufacturing process. Numerous industrial demonstrator parts have been analysed and have shown the software tools to be accurate and a valuable means to improve part quality and reduce development times and costs.
The pressure forming or "thermoforming",of pre-consolidated continuous fibre reinforced thermoplastic (FRTP) sheets offers a most promising fabrication option for structural components in industries ranging from automotive to manufacturing and aerospace. Modem fibre reinforced thermoplastic polymers offer improved mechanical and physical properties compared to their thermoset counterpart, which makes possible the rapid production of high quality structural components. Current process and part design for thermoforming rely heavily on "trial and error" practices which are costly,inefficient and provide little scope for optimization.
This project will develop numerical software tools which would allow the full CAE (computer aided engineering) of the thermoforming process,including pre-heating analysis of the sheets,full simulation during forming and a complete cooling analysis to predict residual stresses and dimensional stability effects,both of which lagerly govern final part quality. The software tools may be used for parametric investigations,optimization and general design of the part and process prior to prototype tool construction and prototype testing.
Substantially reduced manufacturing costs and faster "design-to-product" times would be a result. The availability of the proposed industrially validated,predictive,simulation tools for the thermoforming process are considered essential for the full and successful industrialization of these materials. This represents a logical step in the technological development and industrialization of these materials which has taken place over the past fifteen years.
Funding SchemeCSC - Cost-sharing contracts