|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Frontiers in Solidification Science and Engineering
||Influence of Ta on Solidification Behaviour of Undercooled Ni-Ta Alloys
||Matthias Kolbe, Masoumeh Faraji, Thomas Lierfeld, Gunther Eggeler, Dieter Herlach
|On-Site Speaker (Planned)
The role of Ta inoculation and undercooling on solidification behaviour of Ni-Ta alloys with tantalum addition of up to 4 at% are studied using electromagnetic levitation technique. High speed camera was utilised in-situ to monitor the propagation of the solidification front and to determine dendrite growth velocities. Higher undercooling increased growth velocity of the solidification front for studied Ni98Ta2 and Ni96Ta4 alloys. Morphological changes, from zig-zag to spherical solidification front, are also observed as results of increased undercooling. Microstructure analysis using Electron Back-Scattered Diffraction (EBSD) showed an increased level of twinning up to an undercooling of about 155 K. Higher undercooling leads to grain refined microstructures. The evidences presented in this work suggest that Ta enhances twinning occurrence in undercooled high purity Ni alloys.
||Planned: Supplemental Proceedings volume