Improved fatigue performance for cylinder heads

In order to reduce emissions and increase efficiency of heavy-vehicle diesel engines it is necessary to increase the combustion pressure and temperature. However, this will also infer increased risk for fatigue failures and therefore improved and resource-efficient materials are important for the competitiveness of the Swedish automotive industry.

The suggested project will investigate how foundry process parameters can optimise materials used in the cylinder head regarding its fatigue performance. In particular, the currently used lamellar and compacted graphite irons will be investigated as their properties can be significantly improved by altering parameters as composition, cooling conditions and post heat treatments. The main part of the project will consist of experimental evaluation of new cast iron grades coupled to micromechanical modelling to understand how the fatigue performance depends on the microstructure