**4. Conclusions**

**Figure 20** shows the left width of the weld beads versus the electromagnet voltage (arc deflection) for the different GTAW configurations tested with an average welding current of 200 A. Here the left width also tended to increase with the arc deflection (electromagnet voltage) increase, particularly for the oscillation frequency of 1 Hz. However, for 2 Hz the left width practically remained unchanged with the increase in the electromagnet voltage, tending particularly in the synchronized oscillation case to a small decrease, probably because at 2 Hz the current action times in each of the arc stop positions were shorter. In this case also, the largest left width was obtained for the case of synchronized oscillation at 1 Hz and with large

**Figure 20.** Left width of weld beads versus electromagnet voltage (arc deflection) for different configurations of GTAW

**Figure 21.** Right width of weld beads versus electromagnet voltage (arc deflection) for different configurations of

arc deflection (electromagnet voltage of 30 V).

72 Joining Technologies

with an average welding current of 200 A.

GTAW with an average welding current of 200 A.

According to the conditions used and tests performed, the main findings were:

	- **•** From the evaluation of the synchronism between magnetic oscillation and welding current level and by analyzing the synchronizing device response time, it was observed the efficiency of the synchronization system developed;
	- **•** From the examination of the general effect of the synchronization on weld bead formation, more flexibility to optimize the arc melting capacity was verified in each arc position during oscillation.
	- **•** In general the electrical parameters, including those resulting from the synchronized magnetic oscillation tests, were according to plan, showing the proper/synchronous functioning of the electromagnet control system and of the welding power source;

**•** The synchronized oscillation configuration generally resulted in the largest values of weld bead width. Furthermore, the larger the magnetic deflection used, the greater the total width resulted;

**Author details**

**References**

Thiago Resende Larquer1

Minas, Minas Gerais, Brazil

and Ruham Pablo Reis2\*

1 Federal Institute of Education, Science and Technology of Triângulo Mineiro, Patos de

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http://dx.doi.org/10.5772/64158

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