Linlin WANG
,
Xin LIN
,
Guolu DING
材料科学技术（英文）
Directional solidification experiments were carried out for succinonitrile-1.0 wt pct acetone alloy with the orientation of dendritic arrays being not parallel to the direction of the temperature gradient. Experimental results show that there exists an allowable range of primary dendritic spacing under a given growth condition. The average primary spacing depends not only on the current growth conditions but also on the way by which the conditions were achieved. The upper limit of the allowable range becomes smaller in comparison with that with <001> direction of dendrite arrays parallel to the direction of the temperature gradient, which means that the history-dependence of dendritic growth is weaker under this condition. The lower limit obtained is compared with a self-consistent model, which shows a good agreement with experimental results.
关键词:
Directional solidification
,
枝晶一次间距
,
历史相关性
冯坚
,
黄卫东
,
林鑫
,
李涛
,
薛玉芳
,
周尧和
金属学报
利用Bridgman装置考察了Al—0．53Zn单相合金在近快速定向凝固条件下的胞晶间距选择规律．结果表明：在给定的温度梯度下，随着生长速度的增大，定向凝固组织均为胞状晶，胞晶间距λ的分布存在一个较宽范围，其最大、最小及平均间距随生长速度v变化的实验规律可表示为：λmax＝948．51v(-0.4961),λmin＝661.16v-0.5015,KGT理论模型较好地预言了近快速定向凝固条件下胞晶平均间距选择的实验规律.台阶变速实验表明，胞晶平均间里的选择具有显著的历史相关性.
关键词:
Al-Zn合金
,
near-rapid directional solidification
,
cellular spacing selection
,
history-dependence
