机械工程材料二
MATERALS FOR MECHANCAL ENGINEERING
2015年3月第39卷第3期Vol，39No,3Mar.2015
焊丝对2A12铝合金焊接接头
组织和力学性能的影响
韩丽娟'，李小欣”，李继承
(1.平高集团有限公司，平顶山467001；2.河南平高电气股份有限公司，平顶山467001)
摘要：对2A12铝合金进行交流钨极氢弧焊接，探讨了ER4043烊丝和BJ-380A焊丝对焊接接头组织、抗拉强度和硬度的影响。结果表明：两种焊丝接头焊缝区均为典型的铸态枝晶组织，晶粒生长方向以弯曲形状重垂直于焊接方向；与ER4043焊丝相比，BJ-380A焊丝接头的热影响区晶界中有更多的强化相析出；两种焊丝接头的抗拉强度均可达到母材的50%以上，拉伸断裂部位均位于热影响区；与BJ-380A焊丝相比，ER4043焊丝接头的强度和硬度更高，杭拉强度达到了母材的 67.9%。
关键调：2A12铝合金；交流钨极氨弧焊丝；抗拉强度；硬度
中图分类号：TG456.7
文献标志码：A
文章编号：1000-3738(2015)03-0032-04
EffectsofWeldingWiresonMicrostructureandMechanical
Properties of 2A12 Aluminum Alloy Welded Joints
HAN Li-juan', LI Xiao-xin’, LI Ji-cheng
(1. Pinggao Group Co. , Ltd. , Pingdingshan 467001,China
2.Henan Pinggao Electrie Co., Ltd., Pingdingshan 467001, China)
Abstract; AC-TIG welding was performed on 2A12 aluminum alloy, the effects of ER4043 and BJ-380A welding wires on microstructure, tensile strength and hardness of welded joints were discussed, The results show that the typical cast dendrite was obtained in the weld seam zone of the joints with the two types of welding wires, and the grain growth direction was perpendicular to the welding direction, Compared with ER4043 welding wire, more strengthening phases precipitated at grains boundaries at heat affected zone of the joint with B-380A weiding wire. The tensile strength of the both welded joints are over 50% of the base metal, and the fracture positions all were located on heat affected zone,. Compared with BJ-380A welding wire, the strength and hardness of the joint with ER4043 welding wire were higher, and its tensile strength up to 67, 9% of the base metal.
Key words: 2A12 aluminum alloy; AC-TIG welding; welding wire; tensile strength; hardness
0引言
铝合金由于密度小、比强度高、耐蚀性好、无磁性、成形性好以及低温性能好等特点而广泛应用于工业领域。2A12(LY12)硬铝合金是一种共晶型高强度硬铝合金，具有优良的综合力学性能，在航空，航天、舰船制造等领域口用于制造各种承受高载荷的零件和结构件，如飞机的骨架、蒙皮、翼肋、翼梁、隔框零件铆钉(2-3等。作为典型的硬铝合金，2A12
收稿日期：2013-12-23；修订日期：2014-11-18
作者简介：韩丽期（1981一），女，山西临汾人，工程师，硕士。·32·
万方数据
铝合金的焊接性较差，主要表现在易氧化、易产生气孔、易产生热裂纹以及接头不等强度等方面，焊接时需要采取一定的工艺措施才能获得性能优良的焊接接头，刘守法等[4利用不同形状的搅拌头对高强度异种铝合金2024-T3与7075-T6进行了揽拌摩擦对接焊，并对焊缝的宏观形貌、硬度及接头的拉伸性能、断口形貌进行了分析；严军等[S)对8mm厚 2A12铝合金板进行了CO激光-MIG(熔化极情性气体保护焊）复合焊接，讨论了焊接电压和焊接速度对焊缝几何参数的影响，认为熔深和母材熔化面积取决于焊接速度，此外他们还研究了接头的显微组