微合金化4043铝合金焊丝焊接接头的组织与性能  

MICROSTRUCTURE AND PROPERTY OF WELDING JOINT WELD WITH MICRO-ALLOYING 4043 WELDING WIRE

作　　者：赵志浩[1] 徐振[1] 王高松[1] 崔建忠[1] 

机构地区：[1]东北大学材料电磁过程研究教育部重点实验室,沈阳110819

出　　处：《金属学报》2013年第8期946-952,共7页Acta Metallurgica Sinica

基　　金：国家自然科学基金项目51004036;教育部基本科研业务费项目N110408005资助~~

摘　　要：在传统4043铝合金焊丝基础上,通过单独和复合添加Mg,Zr和Sc对4043铝合金焊丝进行微合金化,使微合金化焊丝焊后的焊接接头可热处理强化,并对其热处理工艺进行优化.使用传统4043铝合金焊丝和微合金化后的铝合金焊丝进行焊接实验.对比焊后焊接接头的显微组织和力学性能发现,添加0.25%Mg(质量分数)可以改善铝合金焊丝焊后的焊接接头的显微组织,提高焊接接头的抗拉和屈服强度,抗拉强度提高10%,屈服强度提高12%,而延伸率基本保持不变.经530℃,2 h+170℃,6 h热处理后,焊接接头的抗拉强度提高54%,屈服强度提高105%.焊丝中添加Sc和Zr可以明显细化焊缝组织的晶粒,增加热处理后强化相析出数量,提高焊接接头的抗拉和屈服强度.Aluminum alloys have been widely used in civil fields and war industry as structural materials due to their good corrosion resistance, electrical conductivity, thermal conductivity and high specific strength. But there is a serious problem of welding joints softening in welding process, which limits greatly the application of aluminum alloys. It is found that improving the composition of alu- minum alloy welding wire can refine grains and enhance the mechanical properties of welding joints. Of all micro alloying additions to aluminum, Sc offers the greatest potential for developing new light weight structural materials with excellent mechanical properties, good welding performance, desirable corrosion and creep resistance, due to the formation of extremely fine, coherent A13Sc particles, which can effectively refine grains and inhibit recrystallization. This aspect permits to increase the possible use of commercial aluminum alloys. The strengthening mechanism is due to the coherent thermody- namically stable particles with ordered L12 structure. Addition of sufficient amount of magnesium can enhance the nucleation rate of A13Sc. It was shown that clusters of Mg atoms were found at the center of A13Sc particles, suggesting that Mg promotes nucleation of these particles. Moreover, addition of zirconium substitutes for scandium（for up to half of the scandium atoms） to form A13（Sc, Zr） precipi- tates, which are more resistant to coarsening than binary A13Sc precipitates. Micro-alloying aluminum alloy welding wires which can be strengthened by heat treatment were designed by adding Mg, Sc and Zr to the traditional 4043 aluminum alloy welding wire, and the heat treatment process was opti- mized. Welding experiment was carried out using the traditional 4043 aluminum alloy welding wire andmicro alloying aluminum alloy welding wires. properties of welding joints, it was found that After comparing the microstructures and mechanical the mechanical properties of welding joints could be improved when adding 0.25% Mg t

关 键 词：4043铝合金焊丝 微合金化 显微组织 力学性能 焊后热处理 

分 类 号：TG146.2[一般工业技术—材料科学与工程]