LAUSR

Abstract The gas metal arc welding (GMAW) process is employed for coating when speed and high efficiency are required. Cold-wire GMAW is a variation of this process, in which an extra wire is introduced into the electric arc and/or the molten puddle. Parameter adjustment in this process is difficult, because it involves twice as many independent parameters as conventional GMAW. Improved mastery of this technology and its variables is essential for furthering its industrial use broadening its range of industrial uses for application of coatings. In this study, the impacts of cold-wire GMAW process variables on the fillet weld and alloy resistance to wear by pure erosion and cavitation were evaluated. A filler metal was deposited on Stellite™ 6 and 21 cobalt alloys on ABNT 1020 carbon steel sheets in the horizontal position. Coating wear was characterized through analysis of hardness and surface topography. The resulting cobalt alloys exhibited superior erosion resistance. Strengthening of Stellite 21 was verified with the pure erosion assay, while strengthening of Stellite 6 was established with the cavitation assay. Use of multiple wires during welding processes was shown to be necessary to obtain alloy combinations with superior resistance to the combined erosion-cavitation phenomenon.