DEVELOPMENT OF A MICROCONTROLLED SYSTEM FOR ELECTROMAGNETIC ARC OSCILLATION IN GAS METAL ARC WELDING
Diego Raimundi Corradi1; Pedro Paiva Brito2; Leonel Dimas de Abreu2; Ítalo Bruno dos Santos2; José Rubens Gonçalves Carneiro2; William de Melo Silva3; Douglas Roberto Ribeiro da Silva2
1 Centro Universitário Una; 2 Pontifícia Universidade Católica de Minas Gerais; 3 Universidade Estadual Paulista Júlio de Mesquita Filho
doi:10.20906/CPS/COB-2015-1895
Resumo
This research presents the development of an electronic system to control the oscillation of the welding arc by electromagnetism during the GMAW process, enabling the automation of weaving motion and possibility of improving weld quality. The oscillation system is composed of an electronic circuit containing a microcontroller and an H bridge, two electromagnetic coils and two power supplies. The circuit is attached to a tractor, which is responsible for moving the welding torch along the workpiece during the process at constant linear velocity. The coils are fixed to a support attached to the tractor and positioned parallel to the welding direction, producing transverse arc oscillation. The proposed system allows the control of amplitude and frequency of oscillation, the desired values of which are sent to the oscillation system via USB communication from interface created in MATLAB®. The arc can be oscillated at frequencies between 0 and 122 Hz and amplitudes between 0 and 5.6 mm. The system was tested during GMAW welding of austenitic stainless steel AISI 316L, with wire electrode ER308LSi and 97%Ar-3%CO2 shielding gas. The results showed that arc oscillation occurred satisfactorily, ensuring greater control of weld bead geometry as well as improving weld visual aspect. Additionally, for frequencies of oscillation greater than 50 Hz, it is observed complete elimination of finger type penetration.
Palavras-chave: Microcontrolled System; Electromagnetism; Arc Oscillation; Finger Type Penetration; Gas Metal Arc Welding