摘要
本文建立了金属在均质形核和非均质形核及压力作用下凝固时的过冷度与热物性参数之间的关系方程。从而在通常给出的金属热物性参数的基础上,解释了 Flemings给出的金属过冷度的实验结果,并预测了最大过冷度极值为2/3T_m。本文讨论了热物性参数、形核剂、压力作用对过冷度的影响,以及获得深过冷液态金属的途径。本文还给出间接确定固-液界面能或扩散激活能的方法。
Equations between degree of undercooling and thermal properties of metalsin homogeneous nucleation,non-homogeneous nucleation and solidification under pres-sure have been established.Based on conventional data of thermal properties of metals,theexperimental results of degree of undercooling given by Flemings have been explained bythese equations,and they predict that the maximum undercoolings of metals are no morethan 2/3T_m·Furthermore,the effects of thermal properties of metals,foreign nucleation agentand pressure on the degree of undercooling have been discussed,and also the measures toreach super-undercooling of liquid metals have been investigated.Moreover,the indirectmeasures to determine solid-liquid interfacial energy or diffusion activation energy havebeen introduced.
关键词
金属凝固
过冷度
热物性
形核
solidifcation of metals
undercooling
thermal properties
nucleation
