Effect of gravity convection on interface morphology during solidification  

作　　者：DUAN MengMeng CHEN ChangLe LI ZhanYao JIN QuanWei 

机构地区：[1]Shaanxi Key Laboratory of Condensed Matter Structures and Properties,Northwestern Polytechnical University,Xi’an 710072,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2007年第4期531-538,共8页中国科学：物理学、力学、天文学（英文版）

基　　金：the National Natural Science Foundation of China (Grant Nos. 50331040 and 60171043)

摘　　要：An experimental apparatus consisting of a crystal growth room and a crystal growth observation system was developed for the study of the effect of the gravity convection perpendicular to the growth direction on the growth process by use of model alloy succinonitrile (SCN)-5wt%ethanol. It was found that the convection improves the stability of the interface and causes the downstream alternation of the cell growth direction because of the dual effect of the Stokes force and the gravity. The second dendrite arm facing the flow comes into being earlier than that at an- other side when the interface transforms cell to dendrite. Then the dendrite at the side facing the flow comes into being earlier. The second dendrite arm facing the flow grows faster and is more developed than that at another side. In addition, the primary dendrite arm spacing increases and the dendrite tip radius decreases un- der the gravity convection.An experimental apparatus consisting of a crystal growth room and a crystal growth observation system was developed for the study of the effect of the gravity convection perpendicular to the growth direction on the growth process by use of model alloy succinonitrile (SCN)-5wt%ethanol. It was found that the convection improves the stability of the interface and causes the downstream alternation of the cell growth direction because of the dual effect of the Stokes force and the gravity. The second dendrite arm facing the flow comes into being earlier than that at another side when the interface transforms cell to dendrite. Then the dendrite at the side facing the flow comes into being earlier. The second dendrite arm facing the flow grows faster and is more developed than that at another side. In addition, the primary dendrite arm spacing increases and the dendrite tip radius decreases under the gravity convection.

关 键 词：GRAVITY CONVECTION SOLIDIFICATION INTERFACE MORPHOLOGY model ALLOY 

分 类 号：O414.13[理学—理论物理]