New aluminum and aluminum alloy plating pretreatment process

Aluminum and aluminum alloy electrolysis in the electrolyte can form a coating, but the coating binding force is not strong, easy to peel. Therefore, aluminum can be first deposited in the aqueous solution containing zinc oxide compounds and then electroplating, this method is either zinc displacement or deposition. It is also possible to first obtain a thin porous oxide film on the surface of aluminum and aluminum alloys by anodizing the power supply to perform electroplating.

The new process is aimed at the actual defects of the current aluminum alloy plating, combined with the aluminum alloy itself to teach the special physical and chemical properties, based on the original process to improve, the specific advantages are as follows:

1. The process flow is short, and the purity of the aluminum alloy surface is improved by selectively dissolving other metals on the surface layer of the aluminum alloy, and the bond strength of the plating layer is improved.

2. The first use of alkaline activation instead of acidic activation process to completely remove the residual alloy silicon and silica gel in the process of pre-plating treatment, effectively improve the coating binding force.

3. After alkaline activation without direct washing and direct zinc immersion, it can avoid the formation of an oxide layer by exposure to air in the acidic activation and secondary zinc immersion.

4. Just a simple zinc immersion can be, the bond strength of the coating is significantly better than the secondary zinc leaching and complex multi-component cyanogen leaching zinc process.

5. The versatility of the process is almost used for all types of aluminum alloy plating pretreatment.

6. The one-time pass rate of product electroplating is obviously higher than the traditional one. If the evaluation of the bonding strength of the simple plating is good, the product qualification rate is close to 100%.

7. The actual production process is simple and convenient.

8. The actual production of a large-scale automatic production line for a long time has proved that the improved pretreatment of the new aluminum alloy plating is very stable.

9. Facilitate the process improvement based on the traditional aluminum alloy plating process.

10. The use of Haocheng aluminum oxidation power supply can achieve rapid increase in the film speed, shorten the film on time, save resources, to achieve cost-effectiveness.