Apparatus and methods for processing work piece components in which a molten phase is produced by a local energy input from at least one of an electric arc, a jet of combustible gas, an electron plasma, and a laser beam. At least one transducer is included for imparting oscillations having a frequency above 15 kHz. The oscillations can be imparted to one or more of the components, the region of the molten phase, and/or to any filler material that is added to the region of the molten phase. The apparatus and methods can be used with known thermal soldering, welding and cutting methods to improve the quality of weld beads and cut edges that are formed, and to increase the processing rate.
