Abstract
Crystal growth in the undercooled DD3 single crystal super-alloy is investigated in this paper. With the increase of undercooling, two kinds of dendrites are obtained. When ΔT < 30 K, dendrite growth is dominantly controlled by solutal diffusion, and the as-solidified morphologies are similar to the conventional as-cast highly branched dendrites. In the undercooling range of 78–150 K, the severe solute trapping that originates from high dendrite growth velocity weakens the effect of solutal diffusion on the dendrite growth. Thermal diffusion, controlled by heat gradient, instead of solutal diffusion, is found to become the key factor in determining the formation of largely developed fine dendritic morphologies. Furthermore, the measured dendrite arm spacing are explained by employing the current dendrite growth theories.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.