1993 Volume 11 Issue 1 Pages 113-119
In an oxidizing gas welding atmosphere of argon-based Ar-CO2-O2 gas mixture, weldings were carried out, using a popular Fe-Si-Mn electrode wire (YGW 12) and rolled steel for welded structure (SM 400B). Mechanical properties such as ultimate tensile strength and Charpy impact property for the extremely low oxygen steel weld metal which oxygen level is 0.001-0.025 mass/ have been investigated.
The ultimate tensile strength seems to be governed principally by alloy content of weld metal, and small amount of oxygen in weld metal has only a minor effect on the ultimate tensile strength. The higher alloy content, the higher the ultimate tensile strength. The extremely low oxygen steel weld metal has greater tensile property, because of limited amount of oxidation losses of alloying elements such as carbon, silicon and manganese. The Charpy toughness of steel weld metal has been affected by the oxygen content in weld metal. High toughness obtained in two oxygen levels, one is 0.04-0.05 mass% oxygen which is well-known peak and the other is less than 0.002 mass% oxygen. It is very important that the Charpy impact property has been improved in the extremely low oxygen steel weld metal which oxygen level is less than 0.002 mass%.
