The biggest risk in barrel nickel plating production is adding the brightener based solely on feel—without referring to reports, instruments, or the specific stage of the process. Doing so increases brightener consumption and adversely affects the appearance and performance of the coating.
For electroplating plants aiming to reduce costs and improve efficiency, a scientific method of addition is essential.
So how should it be done in practice?
The amount of barrel nickel brightener to add should be determined according to the results of Hull cell test panels.
When plating the same type of workpieces, timed and quantitative additions can be used.
When plating different types of workpieces (for example, blind-hole parts, deep-hole parts, or other complex-shaped parts), the required addition amount should be calculated based on the ampere-hours of electroplating.
The principle for replenishing barrel nickel brightener is to add little and often, so as to minimize changes in the brightener concentration in the plating bath. When adding the brightener, it must also be thoroughly stirred to ensure even distribution. In continuous batch production, it can be added before each tank of products is loaded. The brightener should first be diluted 5–10 times to avoid uneven luster on the plated parts caused by excessively high local concentration, or even increased coating brittleness that makes it prone to peeling.
During use, the brightener undergoes decomposition. When these decomposition products accumulate to a certain concentration in the bath, they can increase the internal stress of the electroplated layer and cause defects such as cracking. In severe cases, this may also lead to anode passivation.
Therefore, choosing a suitable electroplating brightener is especially important. For example, Bigley’s barrel nickel brightener Ni-118 is not only suitable for barrel nickel processes on complex workpieces that require high throwing power, but also produces few organic decomposition products. As a result, plating plants do not need to perform frequent major bath treatments, which helps improve production efficiency and reduce labor intensity.
If you are interested in barrel nickel brighteners, please feel free to contact us at any time.
