As a professional in the field of welding, I can provide you with an in-depth understanding of welding aluminum with AC, and the nuances that come with it.

Welding aluminum is a delicate process that requires precision and the right tools. Traditionally, aluminum is welded using TIG (Tungsten Inert Gas) or MIG (Metal Inert Gas) processes. Both of these methods utilize Direct Current (DC) for the welding process, which is known for its superior control and ability to produce high-quality welds on aluminum. However, the question at hand is whether AC (Alternating Current) can be used for welding aluminum.

Firstly, it's important to clarify that AC welding is not a common practice for aluminum. The reason for this is that AC welding, which alternates its polarity, can lead to issues such as inconsistent welds and a higher likelihood of porosity due to the oxide layer on aluminum. The oxide layer is tenacious and can interfere with the welding process, making it difficult to achieve a clean and strong weld.

However, there are instances where AC can be used for stick welding aluminum. Stick welding, also known as Shielded Metal Arc Welding (SMAW), uses a consumable electrode coated with flux that protects the weld pool from contamination. When using AC for stick welding aluminum, the alternating current can help to break down the oxide layer, which is a significant advantage over DC. This is because the negative half-cycle of the AC can ionize the air and create a more conductive path through the oxide layer, allowing for better arc stability and cleaner welds.

It's also worth noting that stick welding with AC can be more forgiving in terms of technique. While TIG and MIG require a high level of skill and precision, stick welding can be more accessible to beginners and those with less experience. The use of flux in stick welding also helps to stabilize the arc and protect the weld from atmospheric contamination, which can be a significant benefit when welding in less-than-ideal conditions.

Now, let's address the statement that neither TIG nor MIG can weld aluminum in breezy conditions. This is partially true. Both TIG and MIG are sensitive to wind because the shielding gas used in these processes can be easily dispersed by wind, leading to contamination of the weld. However, with proper shielding and wind protection measures, it is possible to perform TIG and MIG welding in less-than-perfect conditions.

In contrast, stick welding with AC can offer some advantages in breezy conditions. The flux coating on the electrode provides a level of protection against wind, making it more suitable for outdoor or less-controlled environments. However, it's still crucial to minimize wind exposure as much as possible to ensure the best results.

In conclusion, while DC is generally preferred for welding aluminum due to its control and quality, there are scenarios where AC stick welding can be effectively used. The key is understanding the properties of the materials and the tools at hand, and adapting your technique to suit the specific conditions of your welding project.

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MIG, which is DC, is much faster than TIG, but it is not nearly as controllable because you cannot melt the base metal without adding filler metal. ... Neither TIG nor MIG can weld aluminum in breezy conditions. However, stick welding aluminum is possible with a DC stick welder and it actually works better than I expected.read more >>