Which aluminum filler metals are the most commonly used?

The most commonly used aluminum filler metals for TIG (GTAW) welding applications are indeed 4043 and 5056. Both of these alloys offer distinct advantages depending on the specific welding application and the types of base metals to be joined.

4043 is primarily silicon-based and is popular for its excellent flow characteristics, which make it easier to achieve clean and smooth welds. Its compatibility with a wide range of aluminum alloys makes it a top choice for general-purpose welding, as it provides good corrosion resistance and weld appearance.

5056, on the other hand, contains a higher magnesium content, which enhances its strength and makes it suitable for applications where higher mechanical properties are required. This filler metal is particularly effective in high-stress environments, such as marine applications or structural components.

The other options, while they contain aluminum alloys, are less common in welding filler applications or are specific to niche markets. For instance, 2024 and 7075 are high-strength alloys that are typically used in aerospace applications and may not be easy to weld. Similarly, 5052 and 6061 are more often used as base materials rather than filler metals in FCAW or MIG processes. The alloys 356 and 319 are more specialized for casting applications