海洋平台支撑板异种金属焊接试验研究  

Experimental Study on Welding of Dissimilar Metals for Offshore Platform Support Plates

作　　者：徐和林 王江华[2] 廖娟 XU Helin;WANG Jianghua;LIAO Juan(Hope College,Southwest Jiaotong University,Chengdu 610400,China;School of Mechanical Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]西南交通大学希望学院,成都610400 [2]四川大学机械工程学院,成都610065

出　　处：《精密成形工程》2024年第9期201-208,共8页Journal of Netshape Forming Engineering

基　　金：四川省重点研发计划(2023YFG0166);国家自然科学基金青年基金(61603238)。

摘　　要：目的结合Q245R/Q690D 2种材料的优势研究其焊接接头性能,获得最优的焊接和后热处理工艺参数。方法以某海洋平台建造为背景,选用E50-6焊丝、J形坡口设计对Q245R/Q690D中厚板多道次焊接进行试验研究。在8、12、16、20 kJ/cm热输入下,对接头进行力学性能测试和微观组织观察;为细化接头组织、提高综合力学性能,对最佳热输入下的接头进行不同温度的后热处理,后热处理温度分别为250、350、580℃并保温2 h,进一步观察接头的性能和微观组织。结果焊态下拉伸断裂均发生在Q245R母材侧,在12 kJ/cm热输入下,焊缝表面硬度在338HV左右,焊缝冲击功为172 J;在20 kJ/cm热输入下,冲击功下降至82.7 J,组织粗大且呈板条状。在250、350℃回火能够降低表面硬度,同时焊缝冲击功较焊态的略有上升,最大增加了21 J;在580℃回火后,内部晶粒粗大,焊缝表面硬度增大,最大为448HV,较焊态的提高了32.5%,同时冲击功显著下降,下降至80 J,下降约53.5%。结论Q245R/Q690D中厚板多道次焊接热输入采用12 kJ/cm为宜,同时焊后对接头进行250~350℃回火并保温2 h为推荐后热处理方式。The work aims to combine the advantages of Q245R/Q690D materials and study their welding joint performance,in order to obtain the optimal welding and post heat treatment process parameters.Based on the construction of a certain offshore platform,the experimental study was conducted on the multi pass welding of Q245R/Q690D medium thick plates with E50-6 welding wire and J-shaped break design.Mechanical property test and microstructure observation were conducted on the joints under 8,12,16,and 20 kJ/cm heat input.In order to refine the joint structure and improve the comprehensive mechanical properties,the joint under the optimal heat input was subject to post heat treatment at different temperatures of 250,350,and 580℃for 2 hours.The properties and microstructure of the joint were further observed.The tensile fracture in the welded state occurred on the Q245R base metal side.Under a heat input of 12 kJ/cm,the surface hardness of the weld seam was around 338HV,and the impact energy of the weld seam was 172 J.When the heat input was 20 kJ/cm,the impact energy decreased to 82.7 J,and the microstructure was coarse and lath like.Tempering at 250 and 350℃could reduce surface hardness while slightly increasing the impact energy of the weld compared to the welded state,with a maximum increase of 21 J.Tempering at 580℃resulted in coarsening of internal grains and an increase in surface hardness of the weld,with a maximum of 448HV,which was 32.5%higher than that at the welded state.At the same time,the impact energy significantly decreased,dropping to 80 J,a decrease of about 53.5%.Based on the comprehensive test results,it is recommended to use 12 kJ/cm as the heat input for multi pass welding of Q245R/Q690D medium and thick plates.At the same time,the recommended post heat temperature is to maintain the joint at 250-350℃for 2 h.

关 键 词：异种金属 焊接接头 多道次焊接 接头性能 Q245R/Q690D 

分 类 号：TG404[金属学及工艺—焊接]