Microstructural Evaluations of Dissimilar A335GR P22 and A312TP304H Joints Using ER-NiCr3 Filler by GTAW

In this study, dissimilar welding of H304TP312A austenitic stainless steel to 22 GR P335A low alloy steel by arc-tungsten-gas method was investigated. ER-NiCr 3 filler metal was selected and used for the above joint. The sound dissimilar welding of A312 TP 304H steel and A335 GR P22 steels were obtained by applying voltage in the range of 14-12 volts, amperage of 70-100 A and welding speed of 40-80 mm /min by GTAW method. According to the results solidification of weld metal in the dissimilar welding of A312 TP 304H steel and A335 GR P22 steel have primary austenite and dendritic structure, and due to the presence of carbide-forming elements in the filler metal, carbide formation is possible. The results of the hardness profile of the welded sample showed that in the base metal region of P22 steel there is the lowest hardness of about 194 Vickers and by moving towards A312 TP 304H steel, the hardness has an increasing trend and reaches 325 Vickers.