The voltage required to ionize (add or remove an electron) a material.

The junction of members or the edges of members that are to be joined or have been joined.

The shape and dimensions of a joint in cross section prior to welding.

The distance the weld metal extends from the weld face into a joint, exclusive of weld reinforcement.

That portion of a joint to be welded where the members approach closes to each other. In cross section, the joint root may be either a point, a line, or an area.