Effect of Welding Position on Low Temperature Impact Toughness of Deposited Metal of Flux Cored Wire

Effects of vertical up and flat welding positions on the microstructure and low temperature impact toughness of deposited metal of E81T1-K2 flux cored wire (FCW) were studied according to ANSI/AWS A5.29-1998 standard. The results show that the low temperature impact toughness of deposited metal in vertical up welding position was 65-71 J higher than that of in flat welding position which was 39-46 J. The ratio of columnar grains in deposited metal formed in vertical up welding was less than that in flat welding, but the width was in the contrary situation. More acicular ferrite can be obtained in the deposited metal in vertical up welding. Compared with the deposited metal formed in flat, the inclusions were much smaller and more uniform in deposited metal formed in vertical up welding, which was beneficial for the nucleation of acicular ferrite.