Influence of Local Microstructure on Stresses, Durability and Fracture Mechanics of Cast Iron Components

Abstract:

Cast iron components show a large variety of different microstructures in dependence on chemical composition, inoculation and cooling conditions. In conventional static and dynamic calculations as well as in fracture mechanics assessment of cast iron components, the influence of local microstructure on the overall behavior of the component is not considered. Usually one material dataset is applied for the whole material. The paper describes recent developments in the field of the prediction of local microstructure and its correlation to local stress-strain, fatigue durability as well as fracture toughness. The benefit of combining casting process simulation with lifetime predictions and fracture mechanics assessment is shown for selected examples. By integrating casting process simulation, microstructure modelling, local material characterization and load analysis, a simulation based approach for predicting the behavior and performance of cast iron components already during the design stage is enabled. Thus, the local assessment helps designers to assess risks and strive for light weight designs before the casting is made.

• Periodical: Materials Science Forum (Volume 925)
• Pages: 264-271
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.925.264
• Online since: June 2018
• Authors: Corinna Thomser*, Jakob Olofsson, Vitalii Gurevitch
• Keywords: Cast Iron, Casting Process Simulation, Durability, Failure Assessment Diagram (FAD), Fatigue, Fracture Toughness, Mechanical Properties, Microstructure, S-N Curves, Woehler Curves

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