Factors affecting the quality of galvanized speed and common
(1) pretreatment is not complete. The surface oxidation film, affect the normal zinc deposits.
(2) conductive adverse. Current consumption on the wire, assigned to the workpiece surface current is too small.
(3) the workpiece high carbon content. High carbon steel, cast iron pieces will reduce the deposition potential of hydrogen, the acceleration of the surface activity of hydrogen evolution, current efficiency is reduced.
(4) the workpiece binding. Galvanized when artifacts caused by local blocked thin coating.
(5) the solution temperature is low. When the corresponding reduced at low temperature distribution of current density, the deposition rate of electroless plating must be reduced.
(6) sodium hydroxide content in the plating solution is on the high side. Sodium hydroxide content of high current efficiency was reduced.
(7) additive content in the plating solution is low. Low additive content will affect the dispersion ability, local too thin coating.
(8) by the plating area is insufficient to estimate the plating distribution of current density is too small.
(9) suspension method is undeserved, workpiece with zinc anode spacing is too big, should be adjusted.
(10) Reduce the deposition potential of hydrogen, hydrogen evolution on the surface of workpiece to accelerate the current efficiency is reduced, thus affecting the zinc deposition rate. Should add the right amount of corrosion inhibitor in acid pickling solution, local area to remove oxide skin too thick to use mechanical method, pickling process for inspection.
(11) anode passivation. Effective area decrease, affect the normal distribution of the electric current.
Low content of sodium hydroxide
(12). If the content of sodium hydroxide on the low side, the current density is not high, the anode passivation.