In cooperation with the University of Twente and major partners such as Boeing, the Thermoplastic composite Research Center (TPRC) in Enschede is conducting research into thermoplastic composites (fibre-reinforced plastics). This ‘material of the future’ is incredibly light, durable, strong, rigid, and impact resistant. Thermoplastics make it possible to achieve much higher production rates than would be possible with thermosetting materials, such as epoxy resins. The only drawback is that there are still occasional issues with the production process. However, discoveries made by Sebastiaan Haanappel (a PhD student at the University of Twente) makes unexpected process-induced defects an obsolete issue. Mr Haanappel notes that “We can now detect about 70% of the distortions and potential defects prior to the actual production process. Our results could lead to a massive breakthrough of this material in the automotive and aircraft industries.”
Sebastiaan Haanappel, who was the first PhD student at the TPRC, investigated the effectiveness of computer simulations in predicting laminate deformations during the stamp forming process. Dr René ten Thije from the AniForm company (a University of Twente spin-off company), who designs the software used for computer simulations, expects to have a user-friendly version ready for the market in a few months’ time. Mr Haanappel used the AniForm simulation software to assess its predictive capabilities and to obtain a profound understanding of the deformation behaviour of the considered composite material. Good agreement was found between the predictions of the model and the results obtained by forming experiments. Sebastiaan Haanappel points out that “70% of the deformations can be predicted by using the AniForm simulation software, provided that the behaviour of the material in question has been thoroughly characterized and described by the model. This also implies that it is possible to predict defects like wrinkling.” Mr Haanappel’s work has shown that forming simulation software has great potential for integration into the product development process. It allows for a relatively quick evaluation of modifications such as the product geometry design, the manufacturing process settings, and the material configuration. It is very important for industry to know whether the envisioned production process will run smoothly for the considered product design. Moreover, it is essential to have a thorough understanding of the material behaviour during the forming process. Given the minimal risk of error ultimately involved, industry may be more inclined to try this relatively new product.
Thermoplastic composites
Thermoplastic composites are fibre-reinforced plastics that are lightweight, stiff, and strong. Thermoplastic composite laminates can be stamp-formed at high temperatures into a variety of shapes. The stamp forming process is characterized by high rates of heating and cooling, which makes this process very appropriate for mass production.
Simulation software
Process simulation tools allow for fast evaluation of the effects introduced by modifications of product design, production process, and material configuration. Sebastiaan Haanappel points out that “It is a big advantage to avoid trial and error in practise, which can be prohibitively expensive.” Once I have obtained my PhD, I will continue my activities at the AniForm spin-off company. Our aim is to lower the threshold of the application of thermoplastic composites, to be achieved by offering support to industry in terms of software, consultancy and advice.”
TPRC
The TPRC was founded in 2009 as an independent research centre in the field of pre-competitive research into thermoplastic composites. The TPRC is now a world leader in this field. The centre works with a wide range of partners, including Boeing, TenCate, Fokker Aerostructures and the University of Twente. Remko Akkerman, Professor of the Production Technology group at the University of Twente’s Faculty of Engineering Technology (CTW), holds the position of Technical Director at TPRC. He manages the centre together with Harald Heerink, the TPRC’s Managing Director. The remaining TPRC staff currently includes seven PhDs, four senior research associates, two technicians and six students performing graduation projects. TPRC also houses the AniForm spin-off company, and offers accommodation for other relevant start-ups.
PhD defence
Sebastiaan Haanappel has defended his doctoral dissertation on April 12th 2013, in the Waaier building, University of Twente, Enschede. His thesis and chief supervisor is Professor Akkerman from the Faculty of Engineering Technology (CTW). The PhD thesis entitled “Forming of UD fibre-reinforced thermoplastics: a critical evaluation of intra-ply shear” is available on request from m.vanhillegersberg@utwente.nl .
