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以模型合金丁二腈-5%(质量分数)乙醇作为实验对象,研究了垂直于生长方向的重力对流作用下,固/液界面形态的动态演化过程.结果表明,对流提高了平界面的稳定性,阻止了凸缘的快速发展;Stokes力和重力的双重作用造成了胞晶尖端形态的顺流偏转.胞-枝转变过程中,迎流侧二次臂形成较早,先形成枝晶.枝晶迎流侧二次臂生长较快而且发达,一次间距增大,顶端半径减小.
The dynamic evolution of the solid / liquid interface morphology under gravity convection perpendicular to the growth direction was studied by using 5% (mass fraction) of succinonitrile as the model alloy.The experimental results show that the convection enhances the stability of the flat interface The rapid development of the flange was prevented, and the dual action of Stokes force and gravity caused the forward-deflection of the cell-cell tip shape.During the process of cell-branch transformation, the secondary arm formed on the flow-in side formed earlier and the dendrite formed first. Dendrites on the flow side of the secondary arm growth faster and more developed, once the spacing increases, the tip radius decreases.