The present study shows experimental research of the weld concerning operational,
economic and geometric viability as well as its superficial quality when using MAGCW
(Metal Active Gas – Cold Wire), understood as: MAG welding process with nonenergized
wire or cold wire. For the development of this research, welding MAG and
MAG-CW processes have been used together with 1,2 mm of diameter consumable
solid wires, class AWS E-70S6 and carbon dioxide pure, CO2, as protection gas with
17 l/min release for both processes. Automated welding was performed with
electronic source adjusted in CC+, in constant tension mode, interfaced by a
microcomputer. In both processes the welds were put on steel carbon samples SAE
1020, 76x155x12,7 mm size, with simple disposition passes, pulling and pushing the
voltage arc. The MAG-CW process added cold wire on the electric arc region, fed by
the Tandem and Twin sequential wire shape auxiliary system on plane position. The
variables of influence were: Velocidade de Alimentação do Arame-Eletrodo, VAE,
which varied in three levels: 6; 7,5 and 9 m/min, respectively, Velocidade de
Alimentação do Arame-Fio, VAF, which also varied in three levels: 3; 4 and 5 m/min
combined with VAE. Response variables for experimental evaluation were electric
arc stability, economic features, geometric features and weld superficial quality. The
results demonstrated satisfactory arc stability as well as high production concerning
MAG process and also good superficial aspect of welds. Rising rates obtained by
MAG-CW process demonstrates the superiority due to non-energized wire addition to
the arc. Thus, the MAG-CW process, in comparison with MAG process,
demonstrated superiority concerning the 57% in rate of fusion (RF) for the VAE of 6
m/min, 59 % for the VAE of 7,5 m/min and 53 % for the VAE in 9 m/min. it has also
been observed that the same occurred with the rate of deposition (RD) increasing in
all speed levels: 62% for the VAE in both conditions of 6 m/min and 7,5 m/min and in
57 % for the VAE in 9 m/min. The good performance in the increase of the taxes
obtained by the process MAG-CW demonstrates advantage, with larger evidence in
the acting of these characteristics, in function of the addition of cold wire to the arch.
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