Undercooling and solidification of metallic-like liquid silicon

采用电磁和静电悬浮技术对直径达10 mm的液态Si和Si-Sn液滴进行过冷，测量了晶体生长速度随过冷度的变化。用扫描电镜和X射线衍射分析了凝固态试样的显微组织。在本项目中，生长动力学的变化及其对凝固组织形态的影响将在纯Si和Si-Sn合金中进行研究。将特别关注多面增长向非多面增长的过渡。结果将在过冷熔体中固相自由枝晶生长的现代理论范围内进行讨论。

Electromagnetic and electrostatic levitation technique is applied to undercool liquid Si and Si-Sn drops in diameter up to 10 mm. The crystal growth velocity is measured as a function of undercooling. The microstructures of the as-solidified samples are analysed by Scanning Electron Microscopy and X-Ray Diffraction. In this project the change of the growth kinetics and its influence on the morphology of the solidified microstructure will be investigated in pure Si and Si-Sn alloys as well. Special attention will be placed to the transition of faceted to non-faceted growth. The results will be discussed within modern theory of free dendritic growth of solid phase in undercooled melt.