What happens when the PH value of nickel plating bath rises quickly?

What happens when the PH value of nickel plating bath rises quickly?

Sat Feb 03 14:18:19 CST 2024

The PH value of the nickel plating bath is crucial to the plating process, because it directly affects the quality of the coating and the rate of nickel deposition. A rapid rise in PH is usually not a normal phenomenon and may indicate something wrong with the plating process. Below we will explore the causes of the rapid rise in PH and how to solve them.

Causes of PH increase in nickel plating bath:

1. Alkaline by-products of electroplating reaction: Nickel ions in electroplating may form hydroxide ions (OH-) when reduced at the cathode, which causes the solution to become more alkaline, thereby increasing the PH value.

2. Nickel salt decomposition: Some nickel salts used in nickel plating processes are unstable in the bath and may decompose and generate alkaline by-products.

3. Plating solution pollution: With the extension of plating time, the plating bath may be contaminated by organic and inorganic impurities, which will affect the PH value.

4. Excessive nickel plating additives: Organic additives or auxiliary plating agents used to improve the quality and brightness of the plated layer may sometimes be alkaline, and excessive use will result in an increase in the pH value.

5. Loss of volatile substances: Some of the volatile acids added to the tank (such as boric acid) may be partially volatilized by increasing temperature, reducing the concentration of acidic substances, resulting in an increase in PH value.

Ways to deal with elevated PH:

1. Regularly detect and adjust the PH value: use a PH meter to measure the PH value of the tank regularly, and add the appropriate amount of dilute sulfuric acid or other suitable acidic substances as needed to maintain the PH value in the ideal range.

2. Bath maintenance: The bath is regularly filtered to remove contaminants, especially organic impurities, which may interfere with the bath balance by adsorption on the cathode surface.

3. Adjust the amount of nickel plating additives: calculate and control the amount of additives to ensure that they do not affect the PH value of the tank too much.

4. Adjust the process parameters: ensure that the temperature, current density, stirring and other process parameters of the electroplating operation are stable to prevent too high PH value due to parameter deviation.

5. Consider adding boric acid: It may be necessary to add boric acid to the tank to help maintain a more stable PH.

The rapid increase of PH value of nickel plating bath may affect the quality of plating. It is very important to find and solve this problem in time. By regularly monitoring and maintaining the bath, controlling the use of nickel plating additives and adjusting the plating process parameters according to Bigely product instructions, the bath PH can be managed and the quality and consistency of the coating can be ensured. If the problem persists, it is necessary to contact a Bigely technical engineer for assistance in order to further investigate the potential real cause.