Welding wire and method for welding the aluminum and aluminum alloy and steel

Abstract

The invention discloses a welding wire and a method for applying the welding wire on aluminum and aluminum alloy to be welded with steel. The welding wire (3) takes Al-Si solder as matrix, and then alloying elements of Cu, Mn, Zn and microelements of B, Zr and La are added to form a dedicated welding wire. The method comprises the following steps: K-shaped divided edges are formed on both ends of the aluminum and aluminum alloy (5); the angle of the divided edges is 50 plus or minus 5DEG C; a divided edge of 30 plus or minus 5 and a truncated edge of 1.0-2.0mm are formed on the side of a steel piece (4); the steel piece (4) is fixed on a chucking tool with a cooling device; the butt clearance between the aluminum and aluminum alloy (5) and the steel piece (4) is 1.0-2.0mm; a small-scaled pulse AC TIG welding method is adopted for single-side welding to realize double side shaping; a tungsten electrode (2) is hemispherical; the nozzle (1) of a welding gun is inclined to the aluminum side; and the welding wire (3) is continuously fed. The method can successfully realize the effective and fine quality connection of the aluminum and the dissimilar steel material by electric arc braze welding without clad layer, and has the advantages of simple operation, low welding cost, and stable and reliable welding process.

Description

technical field [0001] The invention relates to the technical field of welding aluminum, aluminum alloy and steel dissimilar materials. Background technique [0002] Due to their low density, high specific strength, good electrical conductivity, thermal conductivity and corrosion resistance, and good mechanical properties at low temperatures, aluminum and aluminum alloys have been widely used in aerospace, automotive, transportation, national defense and other industrial sectors. Wide range of applications. Steel is the most widely used material and has always played a leading role in the manufacturing industry, especially some new types of steel, such as heat-resistant steel, high-strength steel, etc., which have excellent plasticity, toughness, cold and hot processing performance and corrosion resistance. It is widely used in important welding structures such as petroleum, chemical industry, aerospace and nuclear engineering. In order to make full use of the inherent adv...

AI Technical Summary

Problems solved by technology

However, the facts prove that the welding effect of this method is not ideal, the intermediate layer is difficult to avoid the formation of brittle intermetallic compounds, and there are many joint defects, high residual stress and low joint strength

[0011] It can be seen that whether it is a coating, a surfacing layer, or an intermediate layer, it is difficult to obtain high-quality aluminum-steel dissimilar metal joints by arc welding and brazing, and it is difficult to be applied in actual production.

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