【摘要】 在定向凝固的条件下对 Sn－ Pb合金的三次树枝晶生长进行了研究 .探讨了纵向和横向生长的三次树枝晶形态 .给出了三次枝晶间距与工艺参数即温度梯度和生长速度之间的指数衰减关系 .发现纵向和横向三次枝晶在枝晶粗化和间距上存在着明显的差别 ,并探讨了枝晶爬行对枝晶不对称生长的影响 .更多还原

【Abstract】 Investigations have been made on the tertiary dendrite growth of Sn－ Pb alloy in directional solidification. The dendrite morphology in transverse and longitudinal directions has been revealed. The relationship between the dendrite spacing and processing parameters i.e. temperature gradient and growth velocity have been defined. It is found there is an obvious difference in the dendrite spacing and dendrite coursing between transverse and longitudinal dendrite. In addition, the reason for the asymmetric growth is the dendrite climbing in the mushy zone.更多还原