What role can the standard decorative chromium plating process play? Why is it still necessary to add decorative chromium additives? Answering these questions helps us understand the significance of this process for modern industrial production.
Since its development and application, chromium plating has been the most representative type of decorative electroplating. Over the years, chromium plating has almost become a synonym for electroplating. The term "electroplating" often mentioned in spoken language actually refers to chromium plating. This is because the decorative chromium plating layer not only has a high usage rate and a long history of use in various mechanical and hardware products, Moreover, it is deeply favored by the public because it can always maintain a brightness that never changes color.
The standard electrode potential of metallic chromium is actually very close to that of zinc. Chromium is -0.71V and zinc is -0.763V. However, chromium metal has a very important property that its surface is extremely prone to passivation. When it is exposed to the air, a very dense passivation film will form on its surface.
The chemical stability of this passivation film is excellent. Many acids have no effect on it, including nitric acid, acetic acid, sulfuric acid below 30℃, organic acids, hydrogen sulfide, alkali, ammonia, etc. None of these have an effect on the chromium plating layer. Therefore, the surface of metallic chromium can always remain as bright as a mirror. Because the surface potential of chromium is already very positive, chromium plating on the surface of steel is not an anodic coating but a cathodic coating.
The chromium plating layer can dissolve in hydrochloric acid and hot sulfuric acid (above 30℃). Under the action of current, the chromium coating can be anodized and dissolved in an alkaline solution.
However, the standard decorative chromium plating process has a drawback, which is the low current efficiency. To enhance the current efficiency, we can add Bigely decorative chromium additive Cr-8. This not only helps to accelerate production efficiency but also enables operation at high current density, making it convenient to operate.
About us
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 additives. As a famous electroplating additives source manufacturer in China, Bigely has over 20 years' experience in electroplating additives production and own production base of 5000 square meters. We can produce 15,000 tons of electroplating additives every year, which can fully meet the needs of customers.
If you need our high-quality electroplating additives, please contact us. We can provide you samples for test, and also provide a series of services.
