Application of Controlled Magnetic Oscillation to the GMAW Arc, Following Lissajous Patterns as a Weaving Forming the Bead, to Promote Oriented Distribution of Heat and Mass During the Welding Process

Abstract:

Arc deflection by magnetic fields allows to do weld beads weaving movements in mechanized and automatic systems without mechanical devices of oscillation. The mechanic weaving systems already used in some commercial devices mainly for GTA welding. The present paper describes a new way to apply the magnetic arc deflection that can potentially the industrial application to promote the complex weaving by means parametric and mathematics patterns of Lissajous figures. This feature can be a good option as to control, repeatability and productivity to the welding process. Tests have been done use the GTAW and GMAW processes, the latter with short circuit and pulsed-arc transfer modes. The most apparent effects of controlled arc oscillation occurred to the arc length, range, frequency and molten pool with large or small volume characteristic of each process. On GTAW welding the weaving patterns could be obtained to applying lower magnetic field. With short-circuit GMA welding the results were significant but not very evident. On GMA pulsed welding, was obtained great weavings beads.

Key-words:
Weaving on welding; GMAW pulsed; Arc oscillation; Lissajous pattern