What is one consequence of using flux in welding?

Using flux in welding serves several purposes, and one key consequence is that it forms slag that protects the weld. When flux is heated during the welding process, it melts and creates a layer of slag on the surface of the weld pool. This slag acts as a protective barrier, shielding the molten metal from atmospheric contaminants such as oxygen and nitrogen. These contaminants can adversely affect the quality of the weld by causing defects like oxidation or porosity. By preventing these impurities from interacting with the weld pool, the slag significantly contributes to the strength and integrity of the final weld. This protective quality is why the formation of slag is considered a major benefit of using flux in welding processes.