A better understanding of aluminium cast alloys

Aluminium has become an interesting choice for structural components in automotive and aviation industries. In a new PhD thesis from the School of Engineering at Jönköping University, Mohammadreza Zamani has investigated opportunities and challenges on using aluminium cast alloys for different purposes.

“Aluminium is a material with both light weight and high strength, and has many other advantages as well. Depending on the application, it can be mixed with other constituents to give certain characteristics”, says Mohammadreza Zamani.

Improving the strength of aluminium cast materials enables manufacturing of thinner-walled components or even replacing ferrous alloyed components, which reduces the vehicles’ weight. This means lower fuel consumption, less emissions and better use of resources.

“Understanding the role of microstructural features in this family of industrially important materials is the key factor in alloy development. We have systematically studied the role of all microstructures”, says Mohammadreza Zamani.

Since the microstructure governs the properties of these alloys, knowledge about the microstructure allows engineers to control and optimize the properties for different applications. In his thesis, Mohammadreza Zamani has focused on aluminium-silicon (Al-Si) alloys, the most extensively used aluminium cast alloy. He found a strong and complex relation between microstructural features and mechanical properties at different temperatures.

In cooperation with Luleå University of Technology, Mohammadreza Zamani successfully developed and tested a model which shows how the properties and behaviour of the material are influenced by the microstructure, the casting temperature and the cooling rate during the casting process. The model can be used to predict the behaviour of the material without performing costly tests.

The results give a comprehensive overview on the behaviour of Al-Si alloys which is a useful input for foundrymen, engineers as well as scientists.

The project has been conducted in a close collaboration with Kongsberg Automotive, in the context of the CompCAST research project, funded by the Knowledge Foundation and industrial partners, at the School of Engineering. Additional research partners in this research profile were Luleå University of Technology and Bologna University.