Development and validation of predictive methods for multiscale crack propagation in ductile iron alloys

Important results from the project

The project has achieved its objective by establishing and validating new effective characterization methods for defects in cast metals, and by developing prediction models of mean and variance in fatigue performance based on this information. In addition, the project has produced results concerning the influence of specimen size in fatigue crack growth, i.e. the influence of the length scale of the microstructure, and also made a rigorous comparison of different ductile iron grades.

Expected long term effects

The project has significant long-term implications for the design, material selection and dimensioning of load-bearing cast components. That is, in combination with casting technology in relation to the occurrence of casting defects and their impact on fatigue sperformance, designing components with an optimal combination of low weight and high structural integrity. This results in lower environmental impact due to lower material consumption and lower fuel consumption for truck components.

Approach and implementation

The project included both experimental undertakings and theoretical studies of computation methodology which were carried out by its various actors in parallel in different work packages towards a common objective. The time plan was largely followed even though there were delays in material acquission. Notably, the project is considered to have turned out well thanks to the broad common competence of the project participants (Scania, Volvo technology, Epiroc, and Linköping University).