Mechanisms of failure in solid solution strengthened spheroidal graphite cast iron
Spheroidal graphite cast iron (GJS) is popular in numerous fields of application, such as wind energy, due to its excellent casting properties and low cost while offering excellent mechanical properties. In addition to conventional cast irons, the newly developed silicon solid solution strengthened cast irons show a high potential to further increase strength while maintaining high elongation at fracture. However, solid solution strengthened cast iron can exhibit unpredictable brittle fracture behavior depending on temperature and load. Our own preliminary work has shown that this is particularly related to the formation of a B2-superstructure, which is increasingly observed in the ferritic matrix at elevated silicon contents.
In this research project, the local distribution of superstructure inside the ferritic matrix and its influence on failure mechanisms and fracture behavior will be fundamentally investigated and explained. The overall objective of the project is to build an integrated simulation of the formation and evolution of silicon and aluminum microsegregations during solidification and eutectoid transformation as well as their effect on mechanical material properties.
- Fundamental study of the formation of microsegregations and resulting superstructures in solid solution strengthened spheroidal graphite cast iron
- Manufacture, analysis and mechanical characterization of model alloys with different contents of silicon, aluminum and resulting superstructure contents
- Microsegregation simulations and 3D solidification simulation of solid solution strengthened spheroidal graphite cast iron
- Development and verification of a micromechanical model for solid solution strengthened GJS considering microsegregations
- Setup of a simulation chain and application for simulation-based alloy development
Foundry Institute RWTH Aachen University (GI)