What is the term for the metal or alloy used in creating a joint through brazing, soldering, or welding?

The term commonly used to refer to the metal or alloy added to create a joint through processes such as brazing, soldering, or welding is "filler metal." This material is crucial because it acts as a bridge between the base metals being joined, providing additional material that flows into the joint area when heated. During the process, the filler metal melts and bonds with the base metals, forming a strong union upon cooling.

Filler metals can be formulated with various alloying elements to enhance properties such as corrosion resistance, strength, and ductility, aligned with the requirements of the specific application. This distinction is essential, as the effectiveness and characteristics of the joint depend heavily on the choice of filler metal. In contrast, the term "base metal" refers to the primary metals being joined rather than the additional material used to fill the joint. The other terms, "joining metal" and "accessory metal," are less commonly used in welding terminology and do not specifically define the metal used in these joining processes.