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Metal foam is a unique structure and properties of new functional materials, low-nickel high-speed rail foam iron-nickel alloy studied in this paper to generate low cost, stress brittle small, its cheap price, large surface area, high compressive strength, low coefficient of thermal expansion is more suitable for automobile exhaust purification and its related fields. At present, the the electrodeposition foam iron-nickel alloy mainly chloride the system and sulphate bath system, but the chloride system is unstable, easily oxidized, so by comparing the two systems, focusing on sulfate bath system. The process conditions for sulfate-based plating solution is determined by Hull cell test: FeSO4 · 7H2O 350g / L, pH 2.0, temperature 60 ° C, a current density of 8A/dm2. The chloride based bath and sulfate-based bath nickel content in different types of the same concentration of nickel salt coating, corrosion resistance, hardness. Selected by the result of the comparison of the experimental research system of sulphate bath system, the nickel salt of NiSO4 · 6H2O. SEM images of the sulphate bath system as an antioxidant amino acid and manganese chloride, boric acid as a buffer, as a conductive agent sodium alloy surface morphology were also studied various components on the the corrosion performance. Through the study shows that in the sulfate bath system in add 10g / L to 50g / L concentration of NiSO4 · 6H2O nickel content in of 2.5at% ~ 7at% between the coating can be obtained, after the test electrodeposition foam iron-nickel alloy of The process conditions were: FeSO4 · 7H2O 350g / L, NiSO4 · 6H2O 30g / L, pH 2.0, temperature 60 ° C, a current density of 8A/dm2. Investigated by cathodic polarization curves of four kinds of additives (Gd2O3, Pr2O3, Ce2O3, saccharin) co-deposition of iron-nickel alloy cathode process, which Gd2O3 and saccharin can be increased cathodic polarization, Pr2O3 the role of cathodic polarization not significant, Ce2O3 was able to reduce the cathode polarization. The additive is added after the coating is tested by the AFM surface roughness of the smaller surface roughness of the coating after addition of saccharin and cerium oxide, respectively to 77.088 nm and 74.585 nm. Also investigated the influence of different concentrations of additives for the coating hardness, stress, and when adding 0.6g / L of cerium oxide or 0.2 g / L of saccharin, the plating layer having a low internal stress, respectively, of 62.25 Nmm2 and 58.12 Nmm2 using X-ray diffraction (XRD) examine the impact of different additives for coating crystalline form, the result shows that the additive to be added to weaken the iron and nickel (200) diffraction peak.
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