Welding wire for low-temperature steel

This is mainly caused by the \"Chinese characteristics.\" 09MnD and 09MnNiD can be used in China at -70°C, whereas abroad, only low-temperature welding materials with 2.5% Ni can be used at -60°C. Moreover, most of China’s national standards are based on foreign standards (such as the American AWS standards), which results in differences in the minimum temperatures allowed for the base material and welding materials. The standards for welding rods are basically based on those in the United States, but the standards for welding wires take into account China’s actual conditions and therefore do not match the U.S. standards. This often results in the situation where, although standard-type electrodes are available for use, there are no corresponding welding wires to choose from. When selecting welding materials, one should not be limited to NB47015-2011 to avoid being misled. Just as we often see H08A and H08MnA in standards used in combination with corresponding fluxes, H10Mn2 is also commonly used in combination with corresponding fluxes. It seems that in submerged arc welding, only H08A, H08MnA, and H10Mn2 are used. In fact, the original standard specified that welding wires are classified into grades A, B, C, D, and E (with different S and P contents); when used with the same flux, their strength may not differ much, but there can be significant differences in low-temperature impact toughness.