Zn中间层对大直径铝/钢连续驱动摩擦焊摩擦扭矩及接头界面微观组织的影响  

Effect of Zn Interlayer on Friction Torque and Joint Interface Microstructure of Large Diameter Aluminum/Steel Continuous Drive Friction Welding

作　　者：张昌青[1,2] 崔国胜 陈波阳 刘晓 王烨 史煜 ZHANG Changqing;CUI Guosheng;CHEN Boyang;LIU Xiao;WANG Ye;SHI Yu(State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metal,Lanzhou University of Technology,Lanzhou 730050,China;School of Materials Science and Engineering,Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,兰州730050 [2]兰州理工大学材料科学与工程学院,兰州730050

出　　处：《材料导报》2023年第20期147-151,共5页Materials Reports

基　　金：国家自然科学基金(51961025)。

摘　　要：大截面铝/钢复合结构件在连续驱动摩擦焊焊接过程中需要长时间的摩擦才能使界面金属从弹塑性转变为粘塑性状态,长时间的摩擦会导致构件焊缝处产生厚且不均匀的脆性Fe-Al金属间化合物,影响接头的整体性能。摩擦焊过程中铝/钢界面的预置中间层相当于物理扩散屏障,阻碍Fe、Al原子的互扩散,抑制脆性Fe-Al金属间化合物的形成。采用钢侧焊接面添加/未添加Zn中间层的Q235低碳钢棒和1060纯铝棒进行连续驱动摩擦焊接,对比分析焊接过程中的摩擦扭矩、温度以及焊后界面微观组织。结果表明:Zn中间层可以降低焊接过程中的初始峰值扭矩和峰值温度,减小中心区域金属间化合物厚度。添加Zn中间层的接头局部最大抗拉强度提高7.8%,平均抗拉强度提高7%。中心区域的Zn中间层在焊接过程中被摩擦压力挤压到外缘,距中心R/2的区域形成韧性较好的Fe_(2)Al_(5)Zn_(0.4),距中心2 R/3的区域存在Zn元素偏聚现象。Large section aluminum/steel composite structure usually need a long time of friction to make the interface metal from elastic-plastic state to viscoplastic state in the continuous drive friction welding process.The long time friction will lead to the formation of thick and uneven brittle Fe-Al intermetallic compounds at the weld of components,affecting the overall performance of the joint.The preset interlayer of aluminum/steel interface acts as a physical diffusion barrier in the friction welding process,hindering the mutual diffusion of Fe and Al atoms and inhibiting the formation of brittle Fe-Al intermetallic compounds.In this paper,Q235 low-carbon steel rods with/without Zn interlayer and 1060 pure aluminum rods were welded by continuous drive friction welding.The friction torque,temperature in the welding process and microstructure of interface after welding were analyzed.The experiment results show that the Zn interlayer can reduce the initial peak torque and peak temperature during welding and reduce the intermetallic compound thickness in the central region.The local maximum tensile strength and average tensile strength of the joint with Zn interlayer increases by 7.8%and 7%respectively.The Zn interlayer in the central region is extruded to the outer edge by friction pressure in the welding process,and Fe_(2)Al_(5)Zn_(0.4)with good toughness is formed in the region of R/2 from the center,and Zn element segregation exists in the region of 2 R/3 from the center.

关 键 词：Zn中间层 大直径铝/钢接头 摩擦扭矩 微观组织 

分 类 号：TG456.9[金属学及工艺—焊接]