焊接材料对Q355NH钢电弧焊接结构件耐蚀性能的影响  

Effect of Welding Materials on Corrosion Resistance of Q355NH Steel Arc Welding Structure

作　　者：王凌旭 姚瑶 何锦航 王勇 梁宇[3] WANG Lingxu;YAO Yao;HE Jinhang;WANG Yong;LIANG Yu(Guizhou Power Grid Co.,Ltd.Power Science Research Institute,Guiyang 550002,China;China Power Construction Group Guizhou Electric Power Design and Research Institute,Guiyang 550002,China;College of Materials and Metallurgical Guizhou University,Guiyang 550025,China)

机构地区：[1]贵州电网有限责任公司电力科学研究院,贵州贵阳550002 [2]中国电建集团贵州电力设计研究院有限公司,贵州贵阳550002 [3]贵州大学材料与冶金学院,贵州贵阳5550025

出　　处：《热加工工艺》2023年第1期135-140,共6页Hot Working Technology

基　　金：贵州省电力试验研究院项目(066600KK52180066)。

摘　　要：分别采用J422、J506及J506CrNiCu三种焊条对Q355NH耐候钢进行焊接,研究在加速腐蚀环境下Q355NH焊接构件的腐蚀特点与力学性能变化规律。利用扫描Kelvin探针、激光共聚焦显微镜结合微观表征,探索不同焊缝试样的腐蚀差异性,研究了焊接区域与母材的500、1000 h加速腐蚀特点及其对剩余力学性能的影响。结果表明,J422与J506焊条的接头均易出现电偶腐蚀而出现焊缝区优先减薄,且J506焊缝因组织不均匀,其局部腐蚀更为严重。J506CrNiCu焊条与Q355NH基体的电位差较小且锈层生长机制相似,可实现焊接区与母材同步减薄,服役时不易造成应力集中。对腐蚀后的接头进行拉伸试验时,由于测量的接头受力截面积高于实际受力截面积,相比焊前其拉伸强度指标降低。J422, J506 and J506CrNiCu electrodes were used for the welding of Q355NH weathering steel, respectively,and the corrosion characteristics and mechanical properties change of Q355NH welding structure under accelerated corrosion conditions were studied. Scanning Kelvin probe and laser confocal microscope combined with microscopic characterization,the corrosion difference of different weld samples was explored, and the 500 h and 1000 h accelerated corrosion characteristics of welding zone and base metal as well as the influence on the residual mechanical properties were studied. The results show that galvanic corrosion is easy to happen in the joints of J422 and J506 electrodes, thus thinning occurs preferentially in the weld zone. Moreover, the local corrosion of the J506 weld is more serious due to uneven microstructure.The potential difference between J506CrNiCu electrode and Q355NH matrix is small and the growth mechanism of the rust layer is similar, which can realize synchronous thinning of welding zone and base metal, and it is not easy to cause stress concentration in service. In the tensile test of corroded joints, the tensile strength indexes are lower than those before welding,which is related to that the measured cross section area of the joint is higher than the actual cross section area.

关 键 词：耐候钢 焊接腐蚀 电偶腐蚀 

分 类 号：TG178[金属学及工艺—金属表面处理] TG444.1[金属学及工艺—金属学]