AZ31-6061搅拌摩擦焊对接接头的组织与性能  

Microstructure and Mechanical Properties of AZ31-6061 Friction Stir Welding Butt Joint

作　　者：郑晓华[1] 冯俊强 秦凤明 李亚杰[1] ZHENG Xiaohua;FENG Junqiang;QIN Fengming;LI Yajie(Taiyuan University of Science and Technology,Taiyuan 030024,China;Shanxi Jiangyang Chemical Co.,Ltd.,Taiyuan 030024,China)

机构地区：[1]太原科技大学材料科学与工程学院,山西太原030024 [2]山西江阳化工有限公司,山西太原030024

出　　处：《热加工工艺》2022年第7期133-136,共4页Hot Working Technology

摘　　要：采用搅拌摩擦焊对厚度为6 mm的AZ31镁合金和6061铝合金两种板材进行对接试验。采用光学显微镜(OM)、扫描电子显微镜(SEM)及能谱仪(EDS)对异种金属对接接头的微观组织进行观察和分析,采用万能试验机对接头进行力学性能测试。结果表明,在异种合金搅拌摩擦焊过程中铝合金的流动性较差,铝合金后退侧不能形成良好的冶金结合状态。焊缝中心有大量1~3μm厚条带状组织,经能谱结果与镁-铝二元相图分析可以确定条带组织为δ-Mg、α-Al和Al_(12)Mg_(17)组成的混合组织。镁-铝异种金属搅拌摩擦焊接头的抗拉强度为177 MPa,断后伸长率为1.2%,接头力学性能主要由两种金属的塑性流动规律和金属间化合物层的分布决定。AZ31 magnesium alloy and 6061 aluminum alloy plates with the thickness of 6 mm were butt-welded by friction stir welding(FSW) technology. The microstructure of dissimilar metal butt joint was analyzed by means of optical microscope(OM), scanning electron microscope(SEM) and energy spectrometer(EDS). The mechanical properties were tested by using the universal testing machine. The results show that poor metallurgical bonding is found at aluminum alloy side due to the poor liquidity of aluminum alloy during friction stir welding process. A large number of banded structures with thickness of 1-3 μm are found in the weld center. The energy spectrum and magnesium-aluminum binary phase diagram analysis shows that the banded structures are hybrid structure of δ-Mg, α-Al and Al_(12)Mg_(17). The tensile strength and elongation of the magnesium-aluminum dissimilar metal FSW joint is 177 MPa and 1.2%, respectively. The mechanical performance of the joint is mainly depends on plastic flow law of metals and the distribution of the intermetallic compound layer.

关 键 词：异种接头 搅拌摩擦焊 微观组织 金属间化合物 力学性能 

分 类 号：TG453.9[金属学及工艺—焊接]