Hexavalent Chromium vs. Trivalent Chromium

Hexavalent Chromium vs. Trivalent Chromium

The chrome plating process entails the method of applying a thin layer of chromium onto a substrate of metal or alloy through the electroplating process(the passing of electrical currents between electrodes immersed in a chromic acid bath). Because the chrome plating process involves toxic chemicals that need proper disposing of, it is important that the chrome plating process be handled by an experienced professional. Some of the chemicals utilized in the process are also considered carcinogenic.

There are two different chrome plating process methods, Hexavalent & Trivalent, and both are utilized for different purposes. Read on to find out the difference between the two methods and also some of their disadvantages.

Hexavalent Chromium – is the traditional method of chrome plating and is used for decorative and functional finish purposes. This method is done by submerging substrates into a bath of chromium trioxide and sulfuric acid. It helps with corrosion and wear resistance and is also utilized for aesthetic appeal.
Disadvantages: This type of chrome plating produces a lot of hazardous waste and carcinogens that are extremely bad for humans and the environment. It is extremely important taht the byproducts of this chrome plating process are disposed of properly and that safety is of the utmost importance when working with these chemicals. Car manufacturers are even looking to utilize a different type of chrome finish on cars to help reduce the hazardous waste that this process encourages.

Trivalent Chromium – is also another option when it comes to decorative chrome plating and is often viewed as the eco-friendly method. While many in the decorative coating industry feel that Hexavalent chrome plating is better in terms of results, trivalent plating does offer many of the same benefits, like scratch & wear resistance. This type of plating is also available in a variety of colors and utilizes chromium sulfate or chromium chloride as its main ingredient. This makes the process less toxic but also harder to control.
Disadvantages: This type of chrome-plating is not only harder to control than the alternative option, but the chemicals involved also are more expensive. This makes it the chrome plating process cost-competitive with many other plating methods.

All in all chrome plating should be left to the professionals no matter what process of plating you choose. Properly handling, mixing, exposure, and disposal of chemicals is of utmost importance not only to you as an individual but also to the safety and health of the environment.