In welding, what does the term "spatter" refer to?

The term "spatter" in welding specifically refers to the molten metal that is expelled from the weld pool during the welding process. This phenomenon occurs when intense heat from the welding arc causes parts of the molten weld pool to be ejected, often due to agitation within the pool or from the dynamic nature of the welding environment.

Understanding spatter is crucial for weld quality and cleanup; excessive spatter can affect the overall appearance of a weld and may require additional cleanup work after welding. It can also inform welders about the settings and techniques they are using, as different processes and settings may produce varying amounts of spatter.

While discoloration of the metal after cooling, porous structures in a weld, and excess filler material might be related to welding quality and outcomes, they do not accurately describe the phenomenon of spatter itself.