Development of Submerged Arc Welding Wire for High Strength and High Toughness Pipeline Steel

The wire for high strength and toughness pipeline steel submerged arc welding is developed in this paper,the deposited metals obtained by matching SJ101 and SJ102 type flux,has not only high strength(σ_s≥540MPa) and also has high low temperature toughness (A_KV-10℃≥120 J).This wire fulfills the requirement of high strength(σ_s>500 MPa) pipeline steel to the properties of the deposited metals.Experimental results show that C_eq and P_cm should be higher than 0.38 and 0.17 respectively,which can ensure the high strength and high toughness of the deposited metals.With increasing C,Mn content,the acicular ferrite is increased,and the toughness is improved.O is deleterious to the toughness of deposited metals,with the increasing O content,the toughness is lowered.Higher basicity flux increased the C,Mn contents and lowered the O contents,which made the deposited wetals chemical composition to tend to more suitable and improved the toughness.