Some customers asked that in the production process of using zinc-nickel alloy colored passivator, the passivation film of the workpiece appeared black phenomenon, what is the cause of this?
According to the field experience and the characteristics of the product Zn-324 zinc-nickel alloy colored passivator, this phenomenon is generally a problem of the zinc-nickel alloy plating process, mainly for the following three reasons:
1. The concentration of nickel metal additive 51019 in zinc nickel alloy plating solution is too high. 51019 is the nickel ion required to supplement the plating solution, when the concentration of 51019 is too high, the nickel content in the coating will be high, and the nickel content is greater than 15% when the workpiece passivation film is prone to blackening. Therefore, we should pay attention to controlling the content of nickel metal additive 51019 in the process range.
2, the current density of zinc-nickel alloy plating is too large. The high current density leads to the fast deposition rate of nickel ions, so that the content of nickel ions in the zinc-nickel alloy coating is greater than 15%, which will cause the phenomenon of passivation film color blackening. Therefore, we should pay attention to controlling the current density in the normal range when zinc nickel alloy plating.
3, the temperature of electrogalvanized nickel alloy plating solution is too high. High temperature, especially above 35℃, will promote the rapid deposition of nickel ions, resulting in the content of nickel ions in the zinc-nickel alloy coating is greater than 15%, resulting in the passivation film color black. Therefore, we should pay attention to controlling the temperature of the bath in the normal range during production.
Therefore, in the production process of using zinc-nickel alloy colored passivator, the workpiece passivation film blackening is generally not a problem of passivator, and in the zinc-nickel alloy plating process need to pay attention to the above three points, can effectively avoid the workpiece passivation film blackening, reduce the occurrence of failure.
Why choose Bigely Technology?
Guangdong Bigely Technology Co., Ltd. ,founded in 2003, is a high-tech enterprise integrating R & D，production, sales and service, specializing in the production of electroplating chemicals. As a fast growing electroplating chemicals supplier in China, Bigely Technology has a strong technical service force, a number of engineers have more than 20 years of experience in the electroplating industry, can provide customers with the following services.
Pre-sales: According to the customers' planned plating type and the scale of the future development of plating lines, to provide relevant ancillary services.
In-sales: Sampling analysis, training of on-line and laboratory personnel, testing of each process.
After-sales: SOP development and troubleshooting countermeasures for the whole line, and other customer requirements.
The core raw materials of our products are made of international brand products such as BASF from Germany with high purity and low impurity. The production process is in strict accordance with the requirements of ISO9001 quality management system to ensure the stability of product quality.
If you need our high-quality electroplating additives, please contact us. We can provide you samples to you for test, and also provide a series of services.
