Ongeveer 5 uur geleden - Universiteit Utrecht (UU) - Utrecht
Utrecht University's Faculty of Geociences is looking for 15 Postdoc Researchers. Are you interested? Then please read the full profile and apply.
The Eindhoven University of Technology (TU/e) has the following vacancy PhD student "Predictive modelling of mechanical anisotropy in oriented semi-crystalline polymers based on morphological characteristics" in the Polymer Technology group, Department of Mechanical Engineering.
The PhD student position is available in the Polymer Technology group, and will be supervised by Dr. Hans van Dommelen, Prof. Leon Govaert, and Prof. Gerrit Peters.
The research activities of the Polymer Technology group concentrate on the fundamental understanding of various macroscopic problems in the processing and use of polymer components and products. An important challenge is the establishment of a direct link from processing conditions to mechanical performance; a task that requires the combination of a number of vastly different disciplines, including elements of computational rheology, solid-state rheology, and polymer physics and mechanics. The group has a unique research infrastructure, both from an experimental and computational perspective. The Mechanical Testing Lab offers a large capacity of testing equipment for short-term (impact) and long-term testing (static and cyclic fatigue).
Aim of the PhD project, tasks
For a polymer material, the yield behaviour and the mode and time-scales of failure are strongly influenced by the molecular weight distribution of the polymer, the macromolecular orientation and the thermal history, i.e. factors that are directly connected to processing conditions. The latter is particularly true for semicrystalline polymers in which structural features, such as the degree of crystallinity and crystal type, size and orientation strongly influence their mechanical properties. During processing, a material is subjected to conditions that often result in an oriented microstructure, leading to anisotropic properties. To improve product performance, a fundamental and quantitative understanding of how anisotropic properties, including yield and failure kinetics, depend on the (oriented) structure is required.
In this project, a quantitative structure-property relationship will be developed for flow-oriented semicrystalline polymers, in particular polypropylene (PP), in terms of the fully anisotropic yield kinetics and the underlying oriented macromolecular structure. This will involve the characterization of the slip kinetics for the individual slip systems and their effect on macroscopically anisotropic yield kinetics as well as the behaviour of the oriented amorphous phase. This way, a scale transition between the physical mechanisms of deformation and the macromechanical performance of oriented semicrystalline polymers is obtained.
Talented, enthusiastic candidates with excellent analytical and communication skills holding a university degree (MSc) in Mechanical Engineering, Physics, Materials Science or Applied Mathematics are encouraged to apply. A strong interest in mechanics of materials is required. Experience in multi-scale modelling, micromechanics, and experimental mechanics are of benefit.