Aluminum alloy workpiece must be immersed in transition metal plating, such as immersion zinc, tin, nickel metal, in order to obtain a good combination of plating, most of the current applications in mass production to sink zinc for more than the secondary zinc process is dominant, the sinking of zinc water is generally by the market, with each accounted for half of the market. The maintenance and management of the zinc precipitation agent need to pay attention to the following points:
Temperature of zinc precipitation solution
In the use of zinc precipitation agent, it is best to maintain its temperature between 15 ~ 25 ℃, too high due to zinc and other metal replacement too fast, until the gray and black loose, rough, and even spongy replacement layer, this zinc replacement layer bonding is very poor. And when the temperature is low, the zinc sinking liquid reaction is relatively mild, the amount of zinc and other alloys precipitation is small, zinc and other alloy replacement layer is uniform and dense, corrosion resistance and the bonding of the substrate greatly improved, so many manufacturers always complain about the summer aluminum parts are always love to blister, in fact, aluminum alloy plating, the summer cold machine is an indispensable piece of equipment.
Zinc precipitation time
Zinc sinking time is inversely proportional to the temperature and concentration of zinc sinking solution (especially the concentration of metal ions), in the zinc sinking solution temperature of 15 ~ 25 ℃, the concentration of 20 boeum degrees, the zinc sinking time of ① about 1 minute, ② between 30 seconds, too long will become rent brown porous, densification, uniformity is reduced, affecting the subsequent process.
Concluding remarks
Many people will choose self-mixed zinc precipitation agent, but in the actual application process but found that the quality of the zinc precipitation is not good, it is difficult to provide good bonding for the subsequent plating layer. At this time we need to use Bigely zinc precipitation agent BC-22, the deposited zinc plating layer on the aluminum bite is small, can provide uniform, no pinholes, thin and dense zinc replacement layer, so the bonding with the aluminum is good, and at the same time, can be deposited on the zinc plating layer for subsequent plating layer to lay the foundation for a good bonding force.
Please feel free to contact us if you have any demands for zinc precipitation agent.