3D-Analysis of Fatigue Damage in Superalloys for Turbine Blades

Kurzfassung

The present work uses scanning electron microscopy (SEM) in combination with a three dimensional (3D) analysis of multiple sections, which were produced using focused ion beam (FIB) micromachining to analyze the microstructural features which influence the evolution of microstructure during high temperature fatigue. Microstructural analysis is performed on miniature fatigue samples which were tested at 950°C. Special emphasis is placed on regions close to the specimen surface where the precipitation of topologically closed packed (TCP) phases during fatigue loading is observed. The morphology of TCP phases in this selected region will be investigated, focusing on volume fraction, size distribution, shape and spatial arrangement with respect to microstructural deformation features in the specimen.