Ultrassom na soldagem a arco: uma revis?￡o acerca dos m??todos de aplica?§?￡o e seus efeitos

摘要

In the last decade the introduction of ultrasonic energy in arc welding, in order to increase the performance of welding processes and improve the quality of the welds has been studied intensively. In view of this, in this paper an extensive review of the literature concerning the use of this technique, which is applied mainly in two ways is presented. The first due to mechanical ultrasonic vibration of some element belonging to the welding set, such as the welding electrode, the workpiece or the filler material. The other one respect to the arc ultrasonic excitation due to pulsation of welding current at frequencies above 20 kHz. So, are presented in detail the methods of introduction of ultrasound in welding processes with permanent and consumable electrode, its advantages and limitations, and gains in operational terms, such as arc stability and increased penetration, and metallurgical, such as grain refining, weld homogeneity, improved mechanical properties and reduction of partially diluted zones. Finally, it highlighted the potential of these methods in the improvement of weld properties and application in low weldability materials.