Abstract
A novel method of crystal nucleation and detachment from a vibrating chilling solid surface has been proposed to further increase the proportion of equiaxed grains in the solidification microstructure. Using a transparent NH 4Cl–H 2O alloy, the surface nucleation and evolution behaviors of dendrites were in situ observed. The effects of vibration frequency as well as amplitude on the equiaxed crystallographic morphology were experimentally studied, and the effects of the roughness of solid surface were also considered. The results show that exerting vibration to a chilling metal surface is an effective way to produce a lot of nuclei for forming equiaxed grains microstructure, and with higher vibration frequency and amplitude, much finer equiaxed grains are obtained. Moreover, nucleation on the chilling surface is a much localized behavior, some fixed positions on the chilling surface act as active nucleation sites, of which the number increases with a lowering chilling temperature.
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.