What is the relationship between the current density and the plating solution in the production process using alkaline zinc plating brighteners?
Bigolly Technology made an analysis based on the field experience and the characteristics of the product's alkaline zinc plating brighteners BZ-515,the current density is closely related to the plating solution.
As the concentration and temperature of the plating solution increase, the current density can be appropriately increased,When the temperature is low, the conductivity of the plating solution is poor, the adsorption of the alkaline zinc plating brightener is strong, and the desorption is difficult.At this time, high current density cannot be used, otherwise, the edges of the workpiece will be scorched, and the coating will be mixed with brighteners, which will increase the brittleness and cause bubbling.
When the temperature is high, the adsorption of alkaline zinc plating brightener is weak, the polarization is reduced, A higher current density must be used to improve cathodic polarization, refine the crystallization of the galvanized layer, and prevent the appearance of yin and yang surfaces on the workpiece.
For alkaline galvanized rack plating, the current density can be reduced if the cathode is stationary;If cathodic movement is employed, the current density can be increased.For the barrel plating of alkaline galvanizing, when the barrel plating speed is fast and the opening rate is high, the current density can be appropriately increased.
Generally, the plating solution of alkaline zinc plating brighteners is used. When the temperature is lower than 20℃, the current density is 1-1.2A/dm2;When the temperature is 20-30℃, the current density should be 1.5-2A/dm2;When the temperature is higher than 30℃, the current density needs to be 2-4A/dm2.