Aluminum alloy welding wire special for high-speed train and preparation method thereof

Abstract

The invention discloses an aluminum alloy welding wire special for a high-speed train and a preparation method thereof. The welding wire comprises, by weight, 5%-6% of Mg, 0.1%-0.18% of Ti, 0.15%-0.28% of Cr, 0.08%-0.15% of Mn, 0.01%-0.05% of La, 0.1%-0.18% of Te, 0.01%-0.05% of Bi, 0.1%-0.2% of Er, 0.05%-0.18% of Yb, 0.2%-0.4% of Zr, 0.1%-0.25% of Ag, 0.5%-1.8% of Sn, 0.5%-2% of Mo, 1%-2.5% of W, 0.5%-1.5% of V, less than or equal to 0.3% of Fe and Si, less than or equal to 0.2% of Zn, less than or equal to 0.05% of the single content of other impurity elements, less than or equal to 0.15% of the total content of the other impurity elements and the balance Al.

Description

technical field [0001] The invention relates to the field of welding wire technology, in particular to a special aluminum alloy welding wire for high-speed trains and a preparation method thereof. Background technique [0002] With the development of welding technology, aluminum and aluminum alloy welded structures have been widely used in civil and military fields, such as various chemical containers, vehicles, ships, aircraft, space probes, rockets, etc. Among them, the welding wire is an important factor affecting the weld metal structure, composition, solid-liquidus temperature, corrosion resistance of the weld, thermal cracking and mechanical properties of the base metal near the seam. The internal quality of aluminum alloy welding wire depends largely on the quality of the original aluminum. In the preparation process of aluminum alloy welding wire, the degassing effect of aluminum alloy melting is not good, which will cause the hydrogen content of aluminum alloy weld...

AI Technical Summary

Problems solved by technology

In the preparation process of aluminum alloy welding wire, the degassing effect of aluminum alloy melting is not good, which will cause the hydrogen content of aluminum alloy welding wire to be high, resulting in more pores in the welding process. Defects prone to cracks

At present, the main materials used in high-speed train aluminum alloy car bodies are Al-Mg, Al-Mg-Si, and Al-Zn-Mg alloys. When ordinary ER5356 and ER5183 welding wires are used for welding, the joint strength is often only lower than that of the base metal. 60%-70%, which will be detrimental to the safety of high-speed train operation, especially the fatigue life

Moreover, compared with the imported welding wire, the aluminum alloy welding wire produced in our country has a higher content of hydrogen and oxide inclusions, which seriously affects the quality of the weld.

The welding wire often breaks during the drawing process, mainly due to the high content of oxide inclusions, coarse grains, and dendrite segregation, which lead to a decrease in the plasticity of the aluminum alloy.