|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Defects and Properties of Cast Metals IV
||3D characterization of competitive dendrite growth and on the role of low angle grain boundaries during solidification of single crystal Ni-based superalloys
||Felicitas Scholz, Pascal Thome, Jan Frenzel, Gunther Eggeler
|On-Site Speaker (Planned)
The present work investigates competitive dendrite growth during Bridgman solidification of single crystal Ni-based superalloys of CMSX-4 type. A novel tomographic metallographic approach based on serial sectioning, optical wide-field micrographs and quantitative image analysis was applied to evaluate the growth of over 2500 dendrites in a large specimen volume. Our technique involves Voronoi tessellation analysis of micrographs to study competitive dendrite growth. Special emphasis is placed on crystal mosaicity and the presence of low angle grain boundaries. Distributions of neighbour dendrite coordination numbers and of primary dendrite arm spacings were evaluated. It was found that there is increased extinction and re-emergence activity of dendrites in regions with a higher degree of mosaicity. We discuss our results in the light of the present state of knowledge on competitive dendrite growth and related research on low-angle boundary defects in single crystal superalloys.
||Characterization, Solidification, Other