Welding process is an important part of ship construction, and its artistic level is directly related to the usability and safety of the ship.
Welding wire must be used during welding. The influence of suitable welding wire on welding quality cannot be underestimated.
Welding wire is a wire welding material used as filler metal or at the same time as conductive. In gas welding and gas tungsten arc welding, the wire is used as the filler metal; in submerged arc welding, electroslag welding and other gas metal arc welding, the wire is both the filler metal and the conductive electrode.
In addition to considering good welding process performance, the selection of aluminum and aluminum alloy welding wires should make the tensile strength and plasticity of the butt joint (by bending test) meet the specified requirements according to the requirements of the container. To meet the requirements of impact toughness, for vessels with corrosion resistance requirements, the corrosion resistance of welded joints should reach or be close to the level of the base metal. Therefore, the selection of welding wire is mainly based on the following principles:
(1) The purity of pure aluminum welding wire is generally not lower than that of the base metal;
(2) The chemical composition of aluminum alloy welding wire is generally corresponding or similar to that of the base metal;
(3) The content of corrosion-resistant elements (magnesium, manganese, silicon, etc.) in the aluminum alloy welding wire is generally not lower than that of the base metal;
⑷ When welding dissimilar aluminum materials, the welding wire should be selected according to the base metal with high corrosion resistance and high strength;
⑸ High-strength aluminum alloys (heat-treated reinforced aluminum alloys) that do not require corrosion resistance can use welding wires with different compositions, such as aluminum-silicon alloy welding wires with good crack resistance SAlSi-1, etc. (note that the strength may be lower than the base metal).
