PhD Studentship #01
Tribology of Fiber Reinforced Elastomers and Thermoplastics
- Sustainable Elastomers & Thermoplastics by Short-Cut Fiber Reinforcement -
The University of Twente is an entrepreneurial research university. It was founded in 1961 and offers education and research in areas ranging from public policy studies and applied physics to biomedical technology. The University has approximately 2700 employees and 8000 MSc and BSc students and is the Netherlands' only campus university.
The chair of Surface Technology and Tribology within the department of Engineering Technology has a job opening for a PhD-student on the project "Sustainable Elastomers and Thermoplastics by Short-Cut Fiber Reinforcement".
Relatively new short-cut aramid-fiber/elastomer composites show considerably improved tribological properties, in particular cut, ship and chunk resistance in truck tire treads. In addition, the hysteretic properties of aramid-fiber reinforced rubber are greatly reduced, which can immediately be translated in lower rolling resistance of tires and energy or fuel savings of cars equipped with short-cut fiber reinforced tires. Short-cut fiber reinforced tires are therefore very interesting as valuable contributions to a sustainable world.
Important prerequisites for the improvement in properties of the polymers with the aramid fibers are a strong adhesion between fiber and polymeric substrate, respectively a favorable fiber orientation must be established during processing, in order to prevent anisotropy in friction and wear properties. Unfortunately, there are no general controls and experiences available how short-cut fiber reinforced polymers of all sorts need to be designed with respect to their tribological properties for specific applications.
Aim of the project is to develop scientific understanding and generic models for further development of improved short-cut fiber reinforced polymers, thermoplastic and elastomeric. Reliable tribology test methods, against different materials (e.g. metals and asphalt) will be used in combination with state-of-the-art analytical characterization techniques like SEM, TEM and surface analysis. Experimental investigations will be carried out in parallel with the development of models to describe tribological properties, such as friction and wear, on a micro scale, again in relation to the fiber-matrix adhesion and mean fiber orientation.
This PhD opportunity will suit a person with a degree in physical sciences (physics, engineering, materials science, etc.).
You will be based at the Laboratory for Surface Technology and Tribology of the University of Twente and be joining an innovative and diverse group working on Tribology, Surface Technology and Materials. For more information on the research group visit www.tr.ctw.utwente.nl
More information on this PhD studentship can be obtained from
Prof. D.J. Schipper: d.j.schipper@utwente.nl
Please send your application, with Curriculum Vitae, by email to d.j.schipper@utwente.nl.
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PhD studentship #02
Mechanical and thermal activated self healing surfaces made of composite ceramics for mechanical components
SELFSURF
The University of Twente is an entrepreneurial research university. It was founded in 1961 and offers education and research in areas ranging from public policy studies and applied physics to biomedical technology. The University has approximately 2700 employees and 8000 MSc and BSc students and is the Netherlands' only campus university.
The chair of Surface Technology and Tribology within the department of Engineering Technology has a job opening for a PhD-student on the project "Mechanical and thermal activated self healing surfaces made of composite ceramics for mechanical components".
Project
The project is part of a national program on self healing materials financed by the Dutch Ministry of Economic Affairs. Self healing materials are recognized as a new class of engineering materials with the capacity to more or less autonomously repair internal damage.
Oxide ceramics have large potential to be applied in technological applications for their high temperature stability and erosion / corrosion resistance. An important limitation for application is a high coefficient of friction when in contact with a countersurface. Besides that a high coefficient of friction does result in energy losses, it also increases the risk of crack growth, originating from the surface. When oxide ceramics, like Al2O3 and ZrO2 and their composites (ZTA and ADZ), are doped with CuO, it is very interesting to observe that a very thin CuO layer is present on the surface after sintering and machining. Previous research has shown that this thin layer is self – healing when a countersurface is sliding over the surface. The project is focusing on further experimental investigation and modelling of this mechanism, a first application of the developed materials in valve seats of engines as well as optimizing the microstructure for specific applications.
Currently, a Postdoc is working on the project for about half a year. His main task is modelling of mass transport responsible for the layer formation. In the beginning of the PhD project a close cooperation and transfer of knowledge with the Postdoc will take place.
The PhD research comprises experimental preparation and characterisation of the samples as well as further modelling of the contact and self healing behaviour of the surface layer. The focus of the PhD student is on coatings on machine elements and optimalisation of the coating for a specific application.
The performance of the self healing composite oxide ceramic will be quantified in a demonstrator valve / valve seat that has to perform under heavy tribological conditions. The demonstrator applications are engines on Compressed Natural Gas (CNG) and enhanced diesel engines for heavy duty applications. This demonstrator will be developed by TNO Science and Industry.
Profile
You have completed a Masters in mechanical engineering, materials science or equivalent with interest in ceramics and/or tribology. You are proficient in spoken and written English and you have well developed social skills to co-operatively work in a research group.
You will be based at the Laboratory for Surface Technology and Tribology of the University of Twente and be joining an innovative and diverse group working on Tribology, Surface Technology and Materials. For more information on the research group visit www.tr.ctw.utwente.nl
More information on this PhD studentship can be obtained from
Dr. M.B. de Rooij: m.b.derooij@ctw.utwente.nl.
Prof.dr.ir. D.J. Schipper: d.j.schipper@utwente.nl
Please send your application, with Curriculum Vitae, by email to m.b.derooij@ctw.utwente.nl.