Development Of New Wear-resistant Aluminum Alloy Welding Wire Materials

This paper developed a new kind of aluminum alloy welding wire to solve the softening problem of Al-Mg-Si alloy after welding. By comparing the microstructure and mechanical properties of welded joint with the traditional4043wires to determine whether the new wires were advantage over the traditional ones.This new wires were developed by adding small amounts of Mg to the traditional4043wires, we called this new wires4143aluminum alloy welding wires. Took the vertical semi-continuous-extrusion-drawing-surface-treatment method to produce4043and4143wires. Welding6061alloy using these two kinds of wires by AC-TIG.The results showed that adding small amounts of Mg to4043alloy, can significantly improve the strength of cast, and the4143alloy can be strengthed by heat treatment. Adjusting the content of Mg in4143, comparing the mechanical properties of welded joints using4143wires with different Mg additions, the results showed that when adding0.25%Mg to the4043wires, the welded joint attained the best mechanical properties. Comparing the microstructure and mechanical properties of welded joints using4043and4143wires found that using4143wires, the fusion zone of welded joint narrowed, the directivity of columnar grain weakened. Through XRD test, found that the welded joint using4143wires had more Mg2Si precipitated phase than the joint using4043wires. Through mechanical properties test, found that compared with the joint using4043wires, the welded joint using4143wires got more advantage properties, the tensile strength increased by10%, the yield strength increased by12%, while the elongation remained unchanged. Adding0.15%Zr、0.3%Sc、0.15%Zr+0.3%Sc respectively to4043and4143wires, the microstructure analysis showed that adding0.15%Zr separately to4143, can attain the narrowest fusion zone and the best mechanical properties, adding0.3%Sc separately, can got the best bending plastic property.The solution and aging experiment results showed that after530℃/2h+170℃/6h, the hardness and strength of joints recoveried and improved. The tensile strength increase by59%, the yield strength increased by112%of joint using4043wires; the tensile strength increased by101%, the yield strength increased by52%of joint using4143wires. The strength of joints using wires with Zr and Sc addition increased significantly after530℃/2h+170℃/6h heat treatment, the tensile strength reached to300MPa, increased by67%, the yield strength reached to250MPa, increased by130%.Test the wear resistance of surfacing layer of4043and4143respectively, the results showed that compared with4043surfacing layer, the hardness of4143surfacing layer was higher, the friction coefficient was lower, the wear rate was less, so the wear resistance of4143was superior to4043wires.