Which filler materials are particularly susceptible to moisture pickup?

The concern regarding moisture pickup primarily centers around the coatings used on low hydrogen and stainless steel electrodes. These coatings are formulated to enhance the welding performance and provide desirable characteristics during the welding process, such as improved arc stability and reduced porosity. However, they are also known for their hygroscopic nature, meaning they can easily absorb moisture from the environment.

When these electrodes, particularly low hydrogen electrodes, absorb moisture, it can lead to hydrogen-induced cracking in the weld metal, which is a critical issue in welding applications. The presence of moisture in the weld area can cause porosity and reduce the mechanical properties of the weld joint, making it less reliable.

In contrast, while high carbon steel electrodes, aluminum alloy rods, and copper-based fillers may also interact with moisture to a certain extent, they do not have the same sensitivity to moisture pickup nor the associated risks that come with it. Low hydrogen and stainless steel electrodes, with their specialized coatings, are specifically designed to control such issues, but their susceptibility to moisture remains a significant concern for welders.