A future climate neutral society faces requirements for a CO2 emission-free industry and fundamental changes in energy production, transport, and storage. The most promising candidate as green energy carrier is gaseous hydrogen, to substitute oil and natural gas from fossil sources, to achieve a sustainable economy. In its gaseous state, high pressures are required for efficient processing and storage to stay competitive with batteries or natural gas. Compressor technology has received various developments in recent past improving pressure range, delivery rate, service lifetime and adapting designs to fit hydrogen applications. High hydrogen purity for fuel cell energy processing, requires non-lube operation to avoid process gas contamination. State-of-the-art solutions cannot overcome the shortcomings of membrane and hydraulic piston concepts up to 900 bar, such as low delivery rates, whereas the conventional reciprocating piston technology is considered reliable for pressures up to 550 bar. The prospect of high delivery rates and total cost of ownership render reciprocating compressors an important field for research.
Current work aims to investigate new fibre reinforced polymer matrix composites, developed as high-strength piston- and packing-ring materials. These composite materials were characterized by thermo-mechanical testing and their friction and wear behaviour analysed by tribological testing under simulated operation conditions. Additional characterization of microstructure and damage mechanisms by synchrotron tomography and imaging of tribo-layer formation with transmission electron microscopy gave new insights in micromechanical deformation behaviour and self-lubricating properties of such fibre reinforced polymers. Promising candidates like polyimide and polyphenylensulfide matrix polymers, both with carbon fibre reinforcements and addition of polytetrafluorethylen solid lubricant, were identified fitting the requirements of high-pressure hydrogen applications.