Influence On Sc,Zr,Er To The Welding Performance Of5xxx Aluminum Alloy Welding Wire

This paper developed a new kind of aluminum alloy welding wire adding rare metal element to solve the softening problem of5xxx aluminum alloy welding wire after welding. By comparing the microstructure and mechanical properties of the welding joint with the traditional wires adding rare metal element to determine whether the new wires were advantage over the traditional ones.These new wires were developed by adding small amounts of Sc, Zr, Er to the traditional wires. Using the copper casting-extrusion-drawing-surface treatment method to produce aluminum alloy wires. Welding5182and7A52alloy using these kinds of wires by AC-TIG.The results showed that adding small amounts of Sc, Zr, Er to5183and5356aluminum alloy, can significantly improve the extrusion state organization. Comparing the mechanical properties of welded joints of5183and5356with different rare metal element addition, the results showed that when adding rare metal element to the5183and5356aluminum alloy wires, the welded joint attained the best mechanical properties. Comparing the microstructure and mechanical properties of welded joints using aluminum alloy wires found that using5183with rare metal element and5356with rare metal element wires, the fusion zone of welded joint narrowed, the directivity of columnar grain weakened. Through XRD test, found that the welded joint rare metal element had Al3Sc, Al3Ti, AlMg strengthening phase separation.Through mechanical properties test, found that the hardness of the welding joint distribution had the similar trend.The welded joint using5183with rare metal element and5356with rare metal element wires got more advantage properties. In7A52plank mechanical properties test,2#wire adding0.3%Sc had the highest tensile strength,the tensile strength achieves72.5%of the mother materials. In bending test,wires adding0.3%Sc and0.1%Sc+0.2%Er can got the best bending plastic property. In5182plank mechanical properties test,all the breaking location were on the base,the welding performance was good.