新型高性能桥梁钢Q500qE用埋弧焊丝的研制

Development of submerged arc welding wire for new type of high performances bridge steel Q500qE

为了适应我国桥梁建设向高性能方向的发展,以及桥梁结构焊接中埋弧焊的使用情况,本文根据高强钢成分和焊接接头工作条件,研制出了适用于高性能桥梁钢Q500q E专用埋弧焊焊丝。研究结果表明,新研制的XY-H65Q焊丝选用铬镍钼的合金体系,焊丝与XY-AF105Q焊剂配套使用后,焊缝成形美观,脱渣性能优异,焊渣自动脱落,焊道光滑平整,具有优异的操作工艺性能;常规及极限线能量下的熔敷金属力学性能均符合技术要求,其R_m≥650 MPa,R_(p0.2)≥500 MPa,A_(KV)≥60 J(-40℃);其熔敷金属扩散氢含量均在3.4 mL/100 g以下;其脆性转变温度为-60℃以下;在热输入为28.8~35.0 kJ/cm条件下,焊缝强度、韧性等性能稳定。从熔敷金属焊缝组织看,其组织比较细小,主要为针状铁素体,约占85%以上,具有良好的力学性能。

In order to adapt to the development of high performance direction of bridge construction in China,and the application of submerged arc welding in bridge structure welding,based on the composition of high strength steel and the working conditions of welded joint,the special submerged arc welding wire was developed for high performance bridge steel Q500qE.The results showed that the newly developed XY-H65Q welding wire was made of Cr-Ni-Mo alloy.The welding wire had excellent operation performance after mating with XY-AF105Q flu.The mechanical properties of deposited metal under the conventional linear energy and large line energy met the technical requirement,Rm≥650 MPa,Rp0.2≥500 MPa,AKV2≥60 J(-40℃).The diffusible hydrogen content of deposited metal was below 3.4 mL/100 g.The brittle transition temperature was below-60℃.When the welding line energy was 28.8~35.0 kJ/cm,the weld strength,toughness and other properties were stable.From the organization of weld metal,the relatively small organization,mainly for acicular ferrite,accounting for more than 85%.The organization of weld metal had good mechanical properties.