Influence of solidification conditions and alloying elements Re and Ti on micropores formed during homogenization of Ni base single crystal superalloy
Influence of solidification conditions and alloying elements Re and Ti on micropores formed during homogenization of Ni base single crystal superalloy
复制标题
凝固条件及合金元素Re、Ti对镍基单晶高温合金均匀化微孔的影响
DOI：
10.1016/j.jallcom.2018.02.221
复制
发表时间：
2018-05-25
影响因子：
6.2
通讯作者：
Sun, X. F.
中科院分区：
文献类型：
--
作者：
Liu, J. L.;Meng, J.;Sun, X. F.
用X射线层析方法研究了定向凝固过程中的抽拉速度和Re、Ti元素对镍基单晶高温合金CMSX-4在均匀化过程中微孔形成的影响。结果表明，1300℃/3h均质化后，以10 mm/min的速度凝固的样品中5 mm以下的微孔数量比6 mm/min的多。无Re和无钛合金中10 mm以下的微孔数量明显少于普通CMSX-4合金，而15~25 mm之间的微孔数量在15~25 mm之间的微孔数量相对较多。通过一次枝晶间距(PDA)和合金元素偏析比的测量，分析了微孔数量的变化，其原因主要是Re和Ti的反向偏析倾向及其扩散系数的显著差异，PDA的增加也增强了均匀化过程中微孔的形成倾向。(C)2018爱思唯尔B.V.保留所有权利。
The influence of withdraw rate during directional solidification and elements Re and Ti on the formation of micropores during homogenization in Ni base single crystal superalloy CMSX-4 is investigated by Xray tomography method. The results show that the number of micropores below 5 mm in sample solidified at 10 mm/min after homogenization at 1300 degrees C/3 h is greater than that in the case of 6 mm/min. The number of micropores below 10 mm in Re free and Ti free alloys is rather smaller than that of normal CMSX-4 alloy, while the number of micropores between 15 mm and 25 mm in Ti free alloy is relatively greater than that in Re free alloy. The variation of number of micropores is analyzed based on measurement of primary dendrite arm spacing (PDAS) and segregation ratios of alloying elements, the causes are mainly attributed to reverse segregation tendencies of Re and Ti and their remarkable diffusion coefficient difference, the increasing of PDAS also enhances the propensity of micropores formation during homogenization. (c) 2018 Elsevier B.V. All rights reserved.