Restriction or acceleration: Investigation on the remelting/resolidification process during Sn-Ni peritectic solidification in a temperature gradient
Restriction or acceleration: Investigation on the remelting/resolidification process during Sn-Ni peritectic solidification in a temperature gradient
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限制或加速：温度梯度下Sn-Ni包晶凝固过程中重熔/再凝固过程的研究
DOI：
10.1016/j.jallcom.2020.153816
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发表时间：
2020
影响因子：
6.2
通讯作者：
Peng Peng
中科院分区：
文献类型：
--
作者：
Peng Peng
在本工作中，证实了锡镍包晶合金在糊状区二次枝晶臂上的扩散引起的广泛的重熔/再结晶过程。研究了λ(2)与局部凝固时间的关系，结果表明，在包晶反应初期，由于Gibbs-Thomson效应，二次枝晶臂上的重熔/再结晶过程受到了限制。然后，随着定向凝固的进行，这种限制逐渐消失。实验观察表明，二次枝晶臂上的重熔/再结晶可以归因于Gibbs-Thomson效应和温度梯度区熔化(TGZM)效应。进一步分析表明，由于包晶反应和TGZM效应之间的相互作用，温度梯度的作用使得包晶合金的重熔/再结晶过程变得复杂。发现在不同的凝固阶段，包晶反应对重熔/再结晶过程的影响是不同的。通过描述重熔/再结晶过程的扩散控制分析模型，阐明了凝固不同阶段包晶反应对Gibbs-Thomson效应的限制或加速。由于包晶反应、Gibbs-Thomson效应和TGZM效应的相互作用，二次枝晶臂上的重熔/再结晶过程与凝固时间有关。(C)2020爱思唯尔B.V.保留所有权利。
In this work, extensive remelting/resolidification process induced by diffusion on the secondary dendrite arms in the mushy zone was confirmed in a Sn-Ni peritectic alloy. Examination on the dependence of lambda(2) on local solidification time showed that the remelting/resolidification process on secondary dendrite arm by the Gibbs-Thomson effect was restricted at the initial of peritectic reaction. Then, this restriction turns to disappear as directional solidification proceeds. Experimental observation shows that the remelting/resolidification on secondary dendrite arm could be attributed to both the Gibbs-Thomson and temperature gradient zone melting (TGZM) effect. Further analysis showed that this remelting/resolidification process was complicated in peritectic alloys due to interaction between peritectic reaction and the TGZM effect by the imposed temperature gradient. It was found that the influence of peritectic reaction on the remelting/resolidification process was different at different stages of solidification. The restriction or acceleration of the Gibbs-Thomson effect by peritectic reaction at different stages of solidification was clarified by diffusion-controlled analytical model describing the remelting/resolidification process. The dependence of the remelting/resolidification process on secondary dendrite arm on solidification time can be attributed to the interaction between peritectic reaction, the Gibbs-Thomson and TGZM effects. (C) 2020 Elsevier B.V. All rights reserved.