| Sodium cyanide (NaCN) which is virulent is widely used in the cyanide zinc plating process. With our government's requirement to the environment the cyanide zinc plating has been limited to use and required washed out gradually. In this paper we studied the converting from cyanide zinc plating process to cyanide-free.Zinc plating process with the base of selecting and analysing several common uesd complex agents and additives.It's proposed that the lowtoxic complex agents could replace NaCN gradually. The complex agents and additives had been test by electrochemistry method and Hull cell, it's found that the cooperation of complex agents A and brightener B could reach a higher polarization value and a better compatibility in the plating solution with much impurity, so they can be used as the main complex agents and additives in the converting process. The study shows the best condition for converting is NaOH,100～120g/L; complex agents A,15～20ml/L;ZnO:NaOH,1:10～1:11;additives B,2～3ml/L; I,1～4A; Temp,15～40℃.In the experiment, the throwing power, deep hole plating power and anti-erodent have been test. Comparing with cyanide zinc plating and alkali zincate zinc electroplating, it is discovered that the throwing power of the conversion process increase 9% than the cyanide zinc plating; the deep hole plating power is equivalent; the average current efficiency increase 8% approach the alkali zincate zinc electroplating; the stability of solution is fine; the coating is bright, all of that can meet the industry requirements.In sum, this outcome of the study could accomplish the conversion of cyanide zinc plating to cyanide-free cheaply and safely and could have application in the industry.
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