Welding wire prepared from aluminum alloy in use for welding

Abstract

The invention relates to an aluminum alloy welding wire for welding. Its chemical composition and mass percentage (%) are: Mg: 4.0-6.0, Mn: 0.03-0.10, Cr: 0.05-0.10, Si: ≤0.25, Fe: ≤0.40, Cu: ≤0.20, Zn: ≤0.20, Be: ≤0.0003, Ti: 0.10-0.15, and the balance is Al and other unavoidable inclusions. The aluminum alloy welding wire of the present invention has the following advantages: the aluminum alloy smelting process of the welding wire is stable and easy to realize, the wire drawing performance is excellent, and meets the welding technical requirements of industries such as locomotive carriages, chemical pressure vessels, ordnance production, shipbuilding, and aviation; the wire has excellent Excellent welding process performance, welded joints have high strength, good forgeability, and good corrosion resistance.

Description

technical field [0001] The invention relates to an aluminum alloy welding wire for welding. Background technique [0002] Aluminum alloy is widely used in various welding structures and products due to its small specific gravity, high strength, non-magnetic properties, good processing and forming performance, low temperature performance, corrosion resistance and electrical and thermal conductivity, especially suitable for applications with extremely high weight requirements. Harsh aerospace vehicles. The characteristics of aluminum alloy welding are mainly reflected in the following aspects: 1. The affinity between aluminum and oxygen is very high, and aluminum is easily combined with oxygen in the air to form a tight and firm Al 2 o 3 The thin film hinders the melting of the base metal and the good combination between each other, and easily causes slag inclusion. Moreover, the oxide film will also absorb moisture, which will promote the formation of pores and other defec...

AI Technical Summary

Problems solved by technology

3. Poor high temperature plasticity and large linear expansion coefficient

5. The strength of aluminum at high temperature is so low that it cannot support the liquid metal and the weld is poorly formed, and even collapse (or burn through) defects are formed

6. Some aluminum alloys contain alloying elements with low boiling points such as magnesium and zinc. These elements are easily evaporated and burned under the action of high-temperature flames or arcs, thus changing the chemical composition of the weld metal and reducing Properties of Welded Joints

7. When welding aluminum alloys that can be strengthened by heat treatment, due to the influence of welding heat, the mechanical properties of some parts of the base metal near the seam will be reduced

Due to the influence of welding heat, composition segregation or impurity phases often occur on the grain boundary, thereby reducing the corrosion resistance of this area

[0003] When aluminum alloys are welded by fusion welding, the main problems faced are pores in the weld, welding hot cracks, equal strength between the welded joint and the base metal, etc. It can be seen that aluminum alloys are more difficult to weld than ordinary metals