摘要
在不同磁场强度和不同温度梯度条件下,对纯度为99.927%的丁二腈定向凝固时的生长过程进行实时观察。测算不同实验条件下丁二腈的枝晶生长速度,同时对固液界面的温度变化进行测量。在磁场强度和温度梯度不变时,随着时间的推移,枝晶生长速度逐渐减慢;在磁场强度不变的条件下,随着温度梯度的增大,丁二腈枝晶生长速度加快;温度梯度不变时,随着磁场强度的增大,丁二腈枝晶生长速度减慢。枝晶生长速度发生变化的原因是磁场环境影响了丁二腈枝晶生长的凝固过冷度和吉布斯自由能,枝晶生长的驱动力受到影响,因此枝晶生长速度发生变化。
In the condition of different magnetic fields and temperature gradient,the directional solidification of 99.927%SCN growth process was observed in real time.The dendrite growth rate of SCN was measured in different experimental conditions,and the temperature change of solid-liquid interface was measured.When the magnetic field and temperature gradient are not changed,the growth rate of dendrites slows down gradually with time;when the magnetic field is not changed,the growth rate of dendrites increases with the increase of temperature gradient;when the temperature gradient is not changed,the growth rate of dendrites slows down with the increase of magnetic fields.The reason for the change of dendrite growth rate is that the magnetic fields environment affects the degree of undercooling and Gibbs free energy of the dendrite growth,the driving force of dendrite growth is affected,so the dendrite growth rate changes.
作者
张嘉伟
宋建宇
刘凤国
娄长胜
ZHANG Jiawei;SONG Jianyu;LIU Fengguo;LOU Changsheng(Shenyang Ligong University,Shenyang 110159,China)
出处
《沈阳理工大学学报》
CAS
2020年第2期55-59,共5页
Journal of Shenyang Ligong University
关键词
强磁场
丁二腈
枝晶生长速度
凝固过冷度
定向凝固
high magnetic fields
SCN
dendrite growth rate
undercooling
directional solidification
