|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Frontiers in Solidification: An MPMD Symposium in Honor of Michel Rappaz
||Dendrite Growth Kinetics in Undercooled Melts of Intermetallic Compounds
||Dieter Matthias Herlach, Raphael Kobold, Wolfgang Hornfeck, Matthias Kolbe
|On-Site Speaker (Planned)
||Dieter Matthias Herlach
Electromagnetic and electrostatic levitation are applied to undercool metallic drops. The velocity of rapidly advancing dendrites is measured by a High-Speed-Camera. The Al50Ni50 alloy is studied with respect to disorder trapping that leads to a disordered superlattice structure. Disorder trapping is evidenced by energy dispersive diffraction using synchrotron radiation of high intensity to record full diffraction pattern on levitated samples. Experiments on Ni2B using different processing techniques of varying the level of convection reveal convection-induced faceting of rapidly growing dendrites. Eventually, the growth velocity is measured in an undercooled melt of glass forming Cu50Zr50 alloy. A maximum in the growth velocity – undercooling relation is observed. The analysis of this result allows for determining the activation energy of atomic attachment kinetics at the solid-liquid interface that is comparable to the activation energy of atomic diffusion as determined by independent measurements of the atomic diffusion in undercooled Cu50Zr50 alloy melt.