镍基单晶高温合金的取向控制：定向柱状晶辅助的晶粒选择方法

Hu Songsong, Zhao Yunsong, Bai Weimin, Dai Yilong, Yang Zhenyu, Yin Fucheng, Wang Xinming

School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China.

Key Laboratory of Advanced High Temperature Structural Materials, AECC Beijing Institute of Aeronautical Materials, Beijing 100095, China.

Materials (Basel). 2022 Jun 24;15(13):4463. doi: 10.3390/ma15134463.

The service performance of single crystal blades depends on the crystal orientation. A grain selection method assisted by directional columnar grains is studied to control the crystal orientation of Ni-based single crystal superalloys. The samples were produced by the Bridgman technique at withdrawal rates of 100 μm/s. During directional solidification, the directional columnar grains are partially melted, and a number of stray grains are formed in the transition zone just above the melt-back interface. The grain selected by this method was one that grew epitaxially along the un-melted directional columnar grains. Finally, the mechanism of selection grain and application prospect of this grain selection method assisted by directional columnar grains is discussed.

单晶叶片的服役性能取决于晶体取向。研究了一种由定向柱状晶辅助的选晶方法，以控制镍基单晶高温合金的晶体取向。样品采用布里奇曼技术以100μm/s的提拉速率制备。在定向凝固过程中，定向柱状晶部分熔化，在回熔界面上方的过渡区形成了一些游离晶粒。通过这种方法选择的晶粒是沿着未熔化的定向柱状晶外延生长的晶粒。最后，讨论了这种定向柱状晶辅助选晶方法的选晶机制及应用前景。