(1. 福州大學(xué) 材料科學(xué)與工程學(xué)院，福州 350108；
2. 福建工程學(xué)院 材料科學(xué)與工程學(xué)院，福州 350108)
摘 要: 采用脈沖電沉積方法，通過改變Fe含量獲得不同層錯能的納米晶Ni-Fe合金。采用X射線衍射(XRD)、透射電鏡(TEM) 與拉伸試驗研究納米晶Ni-Fe合金的顯微組織和力學(xué)性能。結(jié)果表明：制備的Ni-Fe合金均為面心立方結(jié)構(gòu)的單相固溶體，平均晶粒尺寸為12~25 nm，且平均晶粒尺寸隨層錯能的減小而減小。納米晶Ni-Fe合金抗拉強度為1361~1978 MPa，斷裂伸長率為9.3%~13.2%，納米晶Ni-Fe合金的抗拉強度和斷裂伸長率均隨層錯能的減小而增加。合金抗拉強度的增加是細(xì)晶強化作用的結(jié)果。隨著Ni-Fe合金層錯能的降低，加工硬化率提高，塑性失穩(wěn)被推遲，從而獲得較高的塑性。
關(guān)鍵字: Ni-Fe合金；納米晶；力學(xué)性能；層錯能
（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
