Thermosolutal convection during cellular arrayed growth of Pb-Sn alloys
作者： S. TEWARI , RAJESH SHAH , M. CHOPRA
DOI: 10.2514/6.1993-262
关键词:
摘要: Thermosolutal convection caused by the solute build up ahead of growing arrays cells and dendrites results in macrosegregation along length Pb-Sn alloy (10 to 58 wt pct Sn) specimens when they are directionally solidified a positive thermal gradient (melt on top, solid below, gravity pointing down). At constant gradient, extent increases with decreasing growth speed as microstructure changes from dendritic, cellular planar. An empirical parameter, effective partition coefficient, obtained dependence longitudinal fraction distance can be used represent macrosegregation.
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