TIG welding, also known as Gas Tungsten Arc Welding (GTAW), is a specialized type of welding that requires the use of a specific gas to help create and protect the weld joint. But what kind of gas do you use for TIG welding? In this blog post, we’ll answer that question and provide some helpful tips on choosing the right gas for your next TIG welding project.
Do you need gas for TIG welding?
Yes, gas is needed for TIG welding because it uses gas to maintain and safeguard the tungsten electrode from environmental contamination, such as nitrogen, oxygen, and hydrogen. It will also require an additional durable arc since the electrode is expected to be conserved at a highly controlled range from the workpiece.
So, What Kind Of Gas Do You Use For TIG Welding?
You can use these two gases for TIG welding: Argon (Ar) and Helium (He). You can put Helium in to improve the weld pool’s penetration ability and fluidity.
However, pure Argon is the most commonly used shielding gas for TIG welding. This is because it applies to any element that can be TIG welded.
Using pure Argon gives a more reliable and narrow welding arc, extraordinary arc ignition, and moderately soft heat infusion and penetration. These peculiarities make pure Argon acceptable and the fittest for most TIG welding applications. Generally, it is the only shielding gas that professional and hobby welders need.
Can you use 75 argon 25 CO2 to TIG weld?
It is not advisable to use this mix for TIG. It’s not a suitable gas because your tungsten electrode will burn out immediately. More often than not, welders use pure Argon as shielding gas, while the combination of Argon and CO2 gas is used for MIG.
The reason for using pure Argon for TIG welding is to protect the tungsten electrode. In comparison, 75% of Argon and 25% of Carbon Dioxide (CO2) is best used for MIG welding because it enhances weld penetration and flow.
Can I use CO2 for TIG welding?
Carbon dioxide (CO2) is known precisely to be an active gas. It results in oxidation, particularly around tungsten (the electrode used in TIG welding). And oxidizing additions are not utilized because they destroy the tungsten electrode.
Hence, if you consider the word TIG (inert tungsten gas) welding, it signifies that the shielding gas used in TIG welding must be inert and can’t contain any active elements. CO2 works well with MIG welding because it assists in producing a hotter weld reservoir that flows wider and more rapidly.
What type of gas is used for TIG welding aluminum?
Pure argon, or Argon/Helium (Ar/He) mixture, is the best go-to option for TIG-welding aluminum. This addition allows heat to dissipate easily and quickly because of the aluminum.
Nonetheless, when it comes to AC TIG welding, 100% Helium can’t be used because it affects the cathodic cleaning effect. But you can use 100% of Helium with DC TIG welding. However, experts are the only ones recommended to use this practice, and it is not advisable for amateurs.
What gas to use for TIG welding stainless steel?
When tig welding stainless steel, it is always advisable and safe to use pure Argon or Ar/He mixes. However, because there are different categories and kinds of stainless steel (SS), it is best to know the type of stainless steel alloy you’re working with.
This helps you know the suitable shielding gas to apply because if you are welding with a thin SS, you should avoid adding Helium, as it complicates heat administration. It also leads to corrosion resistance loss by the stainless steel and the decolorization of its surface.
What are some TIG Welding Shielding Gas Blends?
There are different types of TIG Welding shielding Gas blends, and here we’ll be looking at some of those mixtures and their uses;
1. A mixture of Argon and Hydrogen (95% and 5%, respectively)
When you use 5% of hydrogen with a mixture of Argon, it strengthens and solidifies the arc, enhancing welding speed and penetration power. Likewise, it cleanses the surface oxides.
2. A mixture of Helium (He) and Argon (Ar)
The popular and most commonly used proportion of this mixture is 75% of He and 25% of Ar. When less Helium is used, even though it improves the stability of the arc, its penetration is low.
Nevertheless, adding more Helium enables you to maximize the available electric current, authorizing the welding of metal thicker than the engine grades. This mixture applies to all forms of metals.
3. A mixture of Argon and Nitrogen (98% and 2%, respectively)
This kind of mixture can be used to weld copper, austenitic stainless steels, super duplex, and duplex, to avoid loss of nitrogen in the weld metal.
For some applications, it may be beneficial to use a combination of both Argon and Helium gases in order to take advantage of each gas’ unique characteristics.
For example, if you’re welding aluminum at high current levels (over 175 A), then adding helium can provide better arc stability while decreasing distortion caused by excessive heat input. Additionally, combining argon with helium can increase penetration depths on thicker materials such as cast iron or stainless steel pipe joints.
However, it’s important to note that using too much helium can cause excessive spatter due to its higher ionization potential compared to argon – so make sure not to overdo it!
What Gas Is Best For TIG Welding?
Argon and Helium are the most universally used shielding gases for TIG welding, or You can utilize a mixture of both. Periodically, we can use the addition of other gases like oxygen, nitrogen, hydrogen, and carbon dioxide. Nevertheless, you must ensure the proper use of these gases so that the addition won’t undermine the quality of the weld.
Conclusion
Experts highly recommend pure Argon for TIG welding. Even though there is another mixture you can apply, you must avoid using oxygen and carbon dioxide (CO2) in your gas mixture. Otherwise, the weld will turn out unpleasant, weak, and porous. If you’re going to use it, ensure it’s only a tiny amount.
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