The First-principles Study on the Occupation Behavior and the Ductility Mechanism of Zr in Ni-Ni₃Al System with Lattice Misfit

Yuxi Wu¹，Wanglin Zhang¹，Jia Guo¹，Jieshan Hou²，Xiuyan Li²，Renzhong Huang³，Xiufang Ma¹，Qianfeng Zhang¹

1. Institute of Molecular Engineering and Applied Chemistry,Anhui University of Technology2. Shenyang National Laboratory for Materials Science,Institute of Metal Research,Chinese Academy of Sciences3. College of Physics Science and Technology,Shenyang Normal University

摘 要：The influence of lattice misfit on the occupation behavior and the ductility effect of Zr in Ni—Ni₃AI alloys were explored.It is found in energy analysis that the preferable site of Zr between Ni sublattice and Al sublattice will change under different lattice misfit,however,the Zr prefers to segregate Ni phase rather than Ni₃AI phase in all lattice misfit range,which makes it impossible for Zr to go into Ni₃AI phase to occupy Al sublattice in Ni—Ni₃AI system.Bond order（BO）analysis shows that the localized ductility effect of Zr differs in different region,and the comparison between Zr-free and Zr-doped BO analysis successfully explain the mechanism of the embrittlement of Ni—Ni₃AI alloys and the ductility effect of Zr.

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