PhD position “Near-net shape spark plasma sintering of self-healing ceramic sealings for hydrogen compressors”

The Advanced Manufacturing Lab of ETH Zürich (am|z) is looking for a PhD candidate to work on an Innosuisse funded project aimed to investigate the near-net shape manufacturing of ceramic sealings for hydrogen compressors via spark plasma sintering (SPS).

Demand for green hydrogen in the EU is growing rapidly, driven by the transition to more sustainable and decarbonized industrial and transport sectors. Hydrogen transport capacity could be significantly increased by using higher pressures, but existing compressors fail prematurely due to overloading of the sealings. Ceramic sealings are attractive in this context since they can withstand higher loads and allow for smaller clearances. However, owing to the brittle nature, high melting point, and high hardness of the ceramics, it is challenging to produce complex ceramic shapes using conventional near-net shape fabrication and machining processes, and a novel production method for the manufacturing of defect-free ceramic sealings with high dimensional accuracy and wear resistance needs to be developed. This project aims to investigate the near-net shape manufacturing of ceramic sealings using hybrid or conventional spark plasma sintering (SPS), where powders are densified under the effect of high electric currents and pressure. To this end, there is on one hand a need to understand the effect of various process parameters on the sintering behaviour and properties of the ceramic materials, and on the other hand, specifically designed SPS tools need to be developed. Furthermore, the tribological properties of the components will be enhanced by local additives and post-sintering laser surface texturing. To mitigate cracks induced by the laser texturing, self-healing elements will be locally introduced.

In the first step, you will conduct sintering experiments to i) study the compaction behavior of the starting ceramic material, ii) determine optimal processing parameters to produce fully dense, crack-free samples and iii) characterize the mechanical and thermal properties of these samples. Through a coupled modelling and experimental approach, you will then determine the optimal die geometry for near-net shape SPS. Finally, multi-material prototypes with local additions of dry-lubricant and self-healing agents near friction-prone surfaces will be manufactured and characterized, in close collaboration with the industrial partner of the project.

Besides research activities, the PhD candidate will also be actively involved in teaching and lab duties.

• Master in Material Science and Engineering or Mechanical Engineering
• Knowledge and experience in ceramics, powder technologies, and material characterization
• Strong communication, organizational, and analytical skills
• Eagerness to learn about new technologies and delve into the underlying scientific concepts
• Proficiency in English; German skills are a plus

Founded in 2020 and led by Prof. Bambach, the am|z group currently employs about 40 people with research activities in additive and hybrid manufacturing processes and advanced process control. We offer a dynamic, interdisciplinary, and international working environment and we strive at fostering collaborative atmosphere. The Department of Mechanical and Process Engineering at ETH Zurich offers doctoral students an excellent program of studies with international accreditation.