Viability of Application of the Double Layer Technique in Welding Multiple Passes for Vehicle Structure and Heavy Haul Machinery

The maintenance and manufacture of Chassis have been used of more noble materials in the welding applied to the most critical points. In this sense, this study presents the results of some researches developed with ASTM A182 F22 structural steel (a low alloyed steel) by the AWS ER 80S-G Wire. For the buttery, the double layer technique was used with "Higuchi" and "modified Higuchi " tests and the application of "decision diagrams" to refine the parameters to be used. In order to verify the efficiency of the mentioned techniques of fabrication, microhardness tests were carried out, the presence of carbides formed at the interface between the filling and buttery was observed, these responsible for microhardness alterations were also observed the presence of undesired structures such as Martensite in the analyzed ZACs. The welding process used was the GMAW with gas Ar2% O2. Results will be presented regarding the analysis of optical microscopy of the ZAC's in the buttery/ base metal interface.