Short fibre-reinforced composites are widely used in automotive industry. Their processing methods are very similar to polymer processing technologies, but adding short reinforcing fibres can bring a large increase in stiffness and strength for a rather low cost. The mechanical behaviour of short fibre-reinforced composites is typically strongly nonlinear, because the use of thermoplastic polymers leads to sensitivity to creep, visco-elastic and visco-plastic behaviour and strong temperature dependence.
The prediction of this behaviour is typically done by using Mean Field Homogenization methods, based on Eshelby and Mori-Tanaka inclusion methods. In those methods, interfacial debonding cannot be taken into account, while it is one of the dominant damage mechanisms in short fibre composites. As an engineering approach, all damage at the fibre/matrix interface is lumped into the matrix properties, which are thus reverse engineered from measurements on the short fibre composite. In this way, the link to the physical damage mechanism of fibre/matrix interfacial debonding is lost.
In UGent-MMS, analytical methods (e.g. variational approach, shear-lag approach, stress transfer methodology) are being developed for matrix cracks and delaminations in composite laminates with continuous fibre reinforcement. Those analytical methods are very fast, yet accurate in terms of stress fields and discontinuities at cracks. In this project, these methods will be applied to interfacial debonding of short fibre composites and implemented into a finite element code, so that the method can be applied to complex industrial geometries. The research group has its own code for Mean Field Homogenization of short fibre composites and a library of advanced material models for the thermoplastic polymer. The candidate will work closely together with two other postdoctoral researchers in the group that are already working in this field of modelling.
Only candidates with a PhD degree or equivalent experience should apply. The candidate should have a strong background in finite element simulation, programming and composite materials.