The growth velocity-undercooling relationship of highly undercooled Ni and Ni-Cu melts
The growth velocity-undercooling relationship of highly undercooled Ni and Ni-Cu melts
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DOI：
10.1080/02670836.2019.1594553
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发表时间：
2019-03
影响因子：
1.8
通讯作者：
X. L. Xu;Y. H. Zhao;H. Hou
中科院分区：
文献类型：
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作者：
X. L. Xu;Y. H. Zhao;H. Hou
利用高速热成像技术对深过冷纯Ni和Ni-Cu合金的凝固速度与初始过冷度的关系进行了系统的研究。对于纯Ni，枝晶生长速度连续增加，在最大过冷度为320 K时达到约52 m s-1的最大值。对于Ni-Cu合金，枝晶生长速度首先连续增加，然后不连续地增加，在300 K时达到约55 m s-1的最大值。生长速度-过冷度曲线中出现的明显不连续性被认为是由迁移的固液界面之前的本体液体中的溶质扩散的有限速度引起的。
Solidification velocities as a function of initial bulk undercoolings were systematically investigated using high speed thermal imaging of highly undercooled pure Ni and Ni-Cu alloy samples. For pure Ni, the dendrite growth velocity increased continuously to a maximum value of about 52 m s−1 at a maximum undercooling of 320 K. For Ni-Cu alloy, the dendrite growth velocity first increased continuously and then discontinuously to a maximum value of about 55 m s−1 at 300 K. A clear discontinuity appeared in the growth velocity-undercooling curve is considered to be caused by the finite speed of solute diffusion in the bulk liquid ahead of the migrating solid–liquid interface.