摘要
用自制的具有可靠变速特性的定向凝固装置，研究了ＭｎＳｂ／Ｓｂ共晶在阶跃增、减速抽拉的变速生长条件下，相间距的变化行为和调节机制。结果表明，当共晶试样以小变速比增速或减速时，相间距λ在一过渡区内逐渐变化，λ对抽拉速度Ｖ呈滞后响应，分别通过不同位置处的分叉、分枝或终结机制调节，相间距选择进程基本是对称的。以大变速比增速生长时，相间距骤然减小，λ对Ｖ的响应无滞后，而减速时λ逐渐增大，λ对Ｖ呈滞后式响应。间距细化是同一位置上的分叉和分枝，逐渐粗化仍以终结为主，增、减速时的相间距选择进程是非对称的。
The phase spacing and regulating mechanism of MnSb/Sb eutectic grown at varying velocity, V , have been investigated using a selfmade solidification apparatus with reliable varying velocity characteristic. The results show that when pulling velocity increases and decreases at low varying velocity ratio, the spacing, λ , varies gradually within transitional region. The response of λ to V retards, but the phase spacing is approximately symmetric. However, the phase spacing decreases abruptly through MnSb branching or multibranching when increasing the velocity at a high varying velocity ratio, presenting a nonretarded response of λ to V . Oppositely, the phase spacing progressively increases through terminating domination when decreasing the velocity at the same ratio, presenting a retardative response of λ to V . In this case, the phase spacing is nonsymetric for varying velocity.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
1999年第2期85-88,共4页
Rare Metal Materials and Engineering
基金
高等学校博士学科点专项科研基金
江苏省应用基础研究计划
关键词
相间距选择
变速生长
定向凝固
MnSb/Sb
共晶
phase spacing, growth at varying velocity, directional solidification, MnSb/Sb eutectic
