Effect of sulfuric acid content on chromium plating

Effect of sulfuric acid content on chromium plating

Mon May 06 08:19:41 CST 2024

In the process of electroplating hard chromium, the content of sulfuric acid has a very important effect on the whole electroplating process. Sulfuric acid not only helps to regulate the conductivity of the plating solution, but also involves the control of the cathode current efficiency, improving the dispersion of chromium ions, and affecting the appearance and properties of the final coating.

The influence of sulfuric acid content on hard chromium electroplating process is as follows:

1. Enhanced conductivity: Sulfuric acid increases the conductivity of the plating solution, contributing to uniform current transfer and more efficient migration of chromium ions to the surface of the part.

2. Cathode current efficiency: Sulfuric acid helps to control the cathode current efficiency during electroplating, if the sulfuric acid content is appropriate, it can improve the deposition rate of chromium, while avoiding the occurrence of other side reactions, such as hydrogen precipitation.

3. Coating quality: High sulfuric acid content will reduce the proportion of chromium chromate in electroplating, which helps to form a smoother and brighter surface. If the sulfuric acid content is too low, the coating may become rough and appear dull.

4. Stress effect: Sulfuric acid content has a considerable impact on the internal stress of the coating. Appropriate sulfuric acid levels reduce stress within the coating, resulting in a stronger and more durable coating.

5. Dispersion capacity: The increase of sulfuric acid content can improve the plating capacity of chromate plating solution, making the plating more uniform, especially on complex shapes of workpieces.

However, too much sulfuric acid may lead to poor color of the coating, while too little sulfuric acid may lead to abnormal structures, such as micro-cracks or other defects, during the deposition of the coating.

Controlling the sulfuric acid content is just a small part of the management of electroplating production. During electroplating, we must control the proportion of components in the electroplating solution and operating conditions to ensure that the electroplating quality and performance meet standards. During the use of Bigely hard chromium additive, the electroplating plant can adjust the process parameters according to specific electroplating requirements and operating standards by referring to the data provided by Bigely technical engineers.

If you are interested in hard chromium additives, please feel free to contact us.