Effects of Complexing Agents on the Corrosion Resistance of Electroless Ni- Fe-P Alloys

Electroless Ni–Fe–P alloys were deposited onto copper substrate from a bath using tri-ammonium citrate and/or tri-sodium citrate as complexing agents. The effects of complexing agents on the corrosion resistance of the alloys were investigated. The variation of the complexing agent leads to the change of corrosion resistance of the alloys due to the composition and the structure change, the alloys obtained with tri-ammonium citrate as complexing agents show better corrosion resistance than those with tri-sodium citrate as complexing agents. The alloys have better corrosion resistance in alkaline solution than in acid solution due to the increasing of polarization resistance.