WIRE FOR WELDING HIGH-CHROMIUM STEEL

摘要

To form a weld metal having improved hot cracking resistance, low temperature cracking resistance, toughness, strength, and corrosion resistance when welding high Cr steels containing 7.5 wt% or more Cr, the filler wire of the present invention has the ratio of Cr equivalent/Ni equivalent of 1.8 to 2.8 and the product of Cr equivalent x Ni equivalent of 100 to 140, where Cr equivalent = Cr + Mo + 1.5Si, Ni equivalent = Ni + 0.5Mn + 30C; and forms a weld metal having a ternary phase microstructure composed of austenite, ferrite and martensite phases during the gas-shielded arc welding. The filler wire of the present invention typically consists of 0.005 - 0.12 wt% C, 0.01 - 1.0 wt% Si, 0.02 - 2.0 wt% Mn, 12.0 - 17.0 wt% Cr, 5.0 - 8.0 wt% Ni, 1.0 - 3.0 wt% Mo, and the balance of Fe and unavoidable impurities, the impurities including 0.03 wt% or less P and 0.01 wt% or less S.