Can You Use MIG Gas for TIG Welding?

Welding is a complex process that requires a deep understanding of the various techniques and the specific requirements for each. One common question that arises is whether it’s possible to use MIG (Metal Inert Gas) welding gas for TIG (Tungsten Inert Gas) welding. The answer to this question is crucial for achieving the best results in welding.

Understanding the Differences Between MIG and TIG Welding Gases

MIG welding typically uses a gas mixture of Argon and CO2 or other active gases, while TIG welding primarily uses pure Argon gas. This difference in gas composition is crucial because the active gases in MIG gas can have a detrimental effect on the TIG welding process.

MIG Welding Gas Composition

MIG welding gas is typically a mixture of Argon and CO2 or other active gases. The Argon provides the inert shielding, while the CO2 or other active gases help to stabilize the arc and improve the weld bead appearance. The specific gas mixture can vary depending on the application and the type of metal being welded.

TIG Welding Gas Composition

TIG welding, on the other hand, primarily uses pure Argon gas. Argon is an inert gas that provides a stable and consistent shielding environment for the weld pool, protecting it from atmospheric contamination and ensuring a high-quality weld.

Why Using MIG Gas for TIG Welding is Not Recommended

can you use mig gas for tig weldinImage source: Mig weld example

Using MIG gas, which contains active gases like CO2, for TIG welding is not recommended due to the potential negative effects on the welding process and the quality of the weld.

Tungsten Electrode Degradation

The active carbon dioxide in MIG gas can cause the tungsten electrode to burn to a nub, affecting the quality of the weld. This is because the active gases in MIG gas can react with the tungsten, causing it to deteriorate more quickly than when using pure Argon gas.

Weld Pool Instability

The active gases in MIG gas can also lead to instability in the weld pool, making it more difficult to control the welding process. This can result in blowing holes in the weld or other defects.

Reduced Weld Penetration

The active gases in MIG gas can also affect the weld penetration, leading to a shallower and less consistent weld profile. This can be particularly problematic when welding thicker materials or when trying to achieve a specific weld profile.

Recommended Gases for TIG Welding

For the best results in TIG welding, it is recommended to use pure Argon gas. Argon is an inert gas that provides a stable and consistent shielding environment for the weld pool, protecting it from atmospheric contamination and ensuring a high-quality weld.

Argon Gas Flow Rates for TIG Welding

The flow rate of Argon gas in TIG welding is relatively low, typically between 10-25 cubic feet per hour (CFH). This is due to the heavier weight of Argon compared to air, which allows for a more concentrated and effective shielding of the weld pool.

Argon Gas Ionization Properties

Argon gas ionizes easily, making it a great choice for welding. Good ionization means a stable electric arc, a narrow arc cone, and a narrow penetration profile, giving a more precise welding experience.

Argon Gas for Welding Nonferrous Metals

Pure Argon gas is a common choice for welding nonferrous metals in TIG welding, such as aluminum, stainless steel, and titanium. The inert nature of Argon gas helps to prevent oxidation and ensure a high-quality weld.

Conclusion

In summary, while both MIG and TIG welding require gas, the type of gas used in each process is different. MIG welding typically uses a mixture of Argon and CO2 or other active gases, while TIG welding primarily uses pure Argon gas. Using MIG gas for TIG welding is not advisable due to the potential negative effects on the welding process and the quality of the weld. To achieve the best results in TIG welding, it is essential to use pure Argon gas, which provides a stable and consistent shielding environment for the weld pool.

References:
Shielding Gases for TIG & MIG Welding: Which Gas is Best?
Can you use the same gas for MIG and TIG?
What’s the Difference Between MIG and TIG Welding Gas?
MIG vs TIG Welding Gas