Composition and Electromagnetic Property of Elctrofomed Ni-Fe Alloys for MEMS

The relationship between coating microstructure and electromagnetic properties of electroformed Ni-Fe alloys was studied.And the optimum process parameters to obtain Ni-20%Fe deposition were as follows:FeSO4·7H2O concentration 6 g/L;pH value 2.5;current density 3.5 A/dm2;electrolyte temperature 55 ℃.The Ni-Fe deposit is bright and compact,the crystal-planes of the plating are (111),(220) and (200).Electrodeposited Ni-20%Fe has a strong paramagnetism effect with the smallest remanence of 0.5 emu.The coercivity show a monotonic decrease with increasing Fe content in deposit,and the saturation magnetization is only 10% of that of the IJ85 permalloy,indicating that the electroformed Ni-20%Fe alloy has good electromagnetic property and could be used in MEMS actuator manufacturing.