The work presented here show comparatively mechanical properties and microstructure of
weld metals employing two welding techniques, an already disseminated, FCAW (arc
welding with cored wire) and the other is innovative, FCAW-AF (arc welding with Adding
Tubular Wire with a cold wire is not energized) at three levels of speed 6, 8 and 10 m / min.
In this process two diameters of the cold wire 0.8 and 1.0 mm were used. The base metal used
was a naval steel ASTM 131 grade A (low carbon) in geometry of plates 150 mm x 300 mm
x 9.5 mm, applied to V-groove (Bisel of 22.5°) with angle 45° summed, with mild opening
of root of 2.4 mm. The weld used was top type with the application of two passes, one root
pass and the pass of finish (or filling). In order to establish of weld conditions 5 types of
destructive were carried out: face transverse bend, tension, impact test (Charpy notched type
V), microhardness and metallographic test. In addition to the non-destructive analysis visual
and penetrating liquid. In general, the results for the process FCAW-CW, show themselves
compatibles, regarding the process FCAW conventional, but some results showed smaller
values of mechanical property. This fact much probably happened due the presence of
discontinuities in the welded joint FCAW-CW. The microstructural characterization presented
similar results to FCAW-CW and FCAW conventional for all energy levels studied.
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