GKOM2020 – Innovative combustion chamber components for large engines in the maritime sector

Subproject: Development and evaluation of quality assurance procedures for the manufacturing process of combustion chamber components with a focus on the hybrid welding process

The subproject under investigation, with the funding code 03SX445D, is part of the BMWi research program for shipbuilding, shipping and marine technology “Maritime Technologies of the Next Generation”. Within the alliance, the focus was on the development of thermally and mechanically highly stressed combustion chamber components for large engines using composite components. Here, the components were combined by using different material combinations, applying the hybrid thermo-mechanical friction welding process, which is new for this size range. The objective was to develop engine components that meet future requirements in terms of use and fuel and contribute to a reduction in fuel consumption and material and manufacturing costs.

As part of the GKOM2020 sub-project, a large engine piston was calculated and designed at the WTZ on the basis of thermo-mechanical hybrid friction welding. Furthermore, destructive static and dynamic, as well as non-destructive material testing methods were applied, further developed and evaluated for applicability. This was done on the basis of many years of experience and by investigating new testing methods (residual stress measurements and computed tomography). Material samples and components up to the finished piston with different material combinations were examined. A piston was tested with regard to piston secondary force load on a testing machine. The obtained results were compared with simulation results and evaluated.

The research project was able to investigate and demonstrate the suitability of thermo-mechanical hybrid friction welding for pistons larger than 240 mm in diameter, including the testing possibilities. The possibility of combining different piston materials opens up new potential in terms of fuel economy and the use of different fuel variants (e.g. diesel, gas, methanol, hydrogen).

Various companies and research institutes from the fields of forging and forming development, forging and friction welding production, engine and machine research and testing, materials and component development, and foundry and materials research have joined forces as joint partners. These are listed below:

• Drop Forge Schneider GmbH Aalen
• MET Motoren- und Energietechnik GmbH Rostock
• Fraunhofer Institute for Machine Tools and Forming Technology IWU Chemnitz
• TU BA Freiberg / Institute for Materials Technology IWT Freiberg
• TU BA Freiberg / Foundry Institute GI

“Funded by the Federal Ministry for Economic Affairs and Energy based on a resolution of the German Bundestag.”

“The responsibility for the content of this publication lies with the author”.