(1. 福州大学 材料科学与工程学院，福州 350108；
2. 福建工程学院 材料科学与工程学院，福州 350108)
摘 要: 采用脉冲电沉积方法，通过改变Fe含量获得不同层错能的纳米晶Ni-Fe合金。采用X射线衍射(XRD)、透射电镜(TEM) 与拉伸试验研究纳米晶Ni-Fe合金的显微组织和力学性能。结果表明：制备的Ni-Fe合金均为面心立方结构的单相固溶体，平均晶粒尺寸为12~25 nm，且平均晶粒尺寸随层错能的减小而减小。纳米晶Ni-Fe合金抗拉强度为1361~1978 MPa，断裂伸长率为9.3%~13.2%，纳米晶Ni-Fe合金的抗拉强度和断裂伸长率均随层错能的减小而增加。合金抗拉强度的增加是细晶强化作用的结果。随着Ni-Fe合金层错能的降低，加工硬化率提高，塑性失稳被推迟，从而获得较高的塑性。
关键字: Ni-Fe合金；纳米晶；力学性能；层错能
（1. College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, China;
2. College of Materials Science and Engineering, Fujian University of Technology, Fuzhou 350108, China）
Abstract:Nanocrystalline Ni-Fe alloys with different stacking fault energies were prepared by changing Fe content using pulse electrodeposition method. The microstructure and mechanical properties of the nanocrystalline Ni-Fe alloys were characterized by XRD, TEM and tensile testing. The results indicate that all the prepared Ni-Fe alloys are face-centered cubic structure, single-phase solid solution with the average grain size in the range of 12-25 nm, and the average grain size decreases with decreasing the stacking fault energy. The ultimate tension strength of the nanocrystalline Ni-Fe alloys is in the range of 1361-1978 MPa and the elongation to failure is in the range of 9.3%-13.2%. Both the ultimate tension strength and the elongation to failure increase with decreasing stacking fault energy. The increase of tensile strength is due to the fine-grain strengthening. For Ni-Fe alloy, with decreasing the stacking fault energy, the work hardening rate increases, and the plastic instability is delayed, consequently higher plasticity is gained.
Key words: Ni-Fe alloy; nanocrystalline; mechanical property; stacking fault energy
