在含三价铬的水溶液中,以氨基乙酸(gly)为配位剂,直流电沉积制备出Fe-Ni-Cr合金箔,研究了电流密度、铬盐浓度对合金箔成分的影响；采用扫描电子显微镜和X射线衍射对合金箔进行表征,并对合金箔的各项性能进行了研究;采用电化学方法对铬电沉积机理进行初探.确定直流电沉积Fe-Ni-Cr合金箔的最佳工艺条件为:电流密度为15A/dm2,铬盐质量浓度为50 g/L,温度为60℃,pH值为1.5.在此条件下可获得厚度为20～30 μm光亮、无裂纹的合金箔,其中Cr、Fe和Ni的质量分数分别为4％～6％、60％～65％、30％～35％.合金箔微观形貌为紧密堆砌的不规则板块状小晶粒;合金箔为纳米晶结构,晶粒尺寸在纳米范围内,主相是Cr与α-Fe或γ-Fe形成的间隙固溶体；合金箔中Cr含量提高,硬度、电阻及耐蚀性均随之提高.通过理论计算gly-Cr3+还原沉积的标准活化能为35.6kJ/mol,该过程由电子转移步骤控制.%Fe-Ni-Cr alloy foils were electrodeposited from the trivalent chromium bath containing glycine as complexing agent. The effects of electrodeposition current density and concentration of trivalent chromium on composition of alloy foil were investigated. The Fe-Ni-Cr alloy foil was characterized by means of SEM( scanning electron microscopy), EDS (energy dispersive spectraneter) and XRD(X-ray diffraction). The properties of alloy foil and the mechanism of trivalent chromium reduction were also studied. The optimal process conditions are followed as that: 50 g/L CrCl3·6H2O, with 15 A/dm2 current density, at 60 ℃ in the solution of pH value 1.5. Fe-Ni-Cr alloy foil with the thickness of 20— 30 μm was obtained with a smooth and uniform appearance, which contains 4%—6%(mass fraction) Cr, 60%—65%Fe and 30%—35%Ni. The results indicated the alloy foil piled up compactly with irregular plate grain and its grain size was less than 100 nm; and the main phases were the α-Fe or γ-Fe interstitial solid solution with Cr. The higher content of Cr in alloy foil, the higher electrical resistance, micro-hardness and anti-corrosion resistance for alloy foil. Furthermore, the activation energy of electrodeposition Cr was calculated about 35.6 kj/mol by means of polarization curve, which demonstrates the rate controlled step is charge transfer process.
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