Title: High Temperature Mechanical Deformation and Fracture Behavior of Nickel Based Super-alloys (module III).
Abstract: The CM 247 alloy is designed primarily for directionally solidified turbine blade and vane applications. Directional solidification (DS) reduces the number of grain boundaries transverse to the primary loading axis, obtaining improved creep resistance. In DS blades the  crystallographic orientation is the preferred orientation along the blade principal axis. During service condition, these components are exposed to severe stress conditions and temperature fluctuation. These service conditions induce low cycle fatigue, creep and creep-fatigue damage in the material. The present proposal aims at studying creep-fatigue interaction behaviour of CM 247 DS nickel base superalloys at temperatures above 750oC and 850oC and studying the microstructural changes through extensive scanning and transmission electron microscopy.