I know you’re wondering what gas is used for TIG welding. I will tell you the answers right here.
When I was growing up, my dad was a welder. He would tig weld using whatever gas came out of the cylinders he had on hand. It just so happened that it was mostly helium and argon.
But I remember asking him why it was that he used argon or helium when other gases were cheaper. That’s when he told me how these gases work in the process of TIG welding.
Learn the shielding gases & different gas blends for TIG welding by reading this article! I will guide you about TIG welding shielding gas in detail in this.
What Gas is Used for TIG Welding?
The most common gas that is used for TIG welding is argon. Argon is a colorless, odorless gas that can be used to create a weld. Argon gas has a very low density and is the best choice for TIG welders who are looking for a clean finish to their work.
Argon can also be used in conjunction with helium. Helium has different characteristics and can improve the quality of your welds.
For example, helium can increase the speed at which your weld cools down after you’ve finished working on it, making it ideal for large projects that require frequent changes of position during welding so that they do not get too hot while they’re being worked on (which would cause them to crack).
Is it Possible to Use the Same Gas for MIG/ TIG?
The short answer to this question is no. It’s impossible to use the same gas for both MIG and TIG because it creates alot of issues for your weld.
For example, if you’re using 25% CO2 or 75% argon gas for MIG welding, those gases are not safe for TIG welding. This combination creates sparks issues that are not good for your weld quality.
Only on one condition, you may use the same gas for both MIG & TIG. If you want to use pure argon for MIG welding aluminum, then you may use 100% argon for TIG weld too.
Because CO2 gas is mostly used in metal inert gas (MIG) welding. This means that the metal being welded is protected from oxidation while it’s being heated up by a constant flow of argon or helium through a nozzle, the shielding gas.
The problem is that CO2 can’t be used with a tungsten electrode, which is what you’d need for TIG welding.
With this technique, the arc between your electrode and workpiece creates its own shielding effect by generating an electric arc that protects both surfaces from oxidation. But since CO2 isn’t conductive, it won’t work here!
Using Argon for TIG Welding
Argon is an inert gas, meaning it doesn’t react with other materials. It’s used in TIG welding because it helps protect the weld from oxidation.
In TIG welding, you use a torch to heat the metal, and then you weld the pieces together with your hands.
When you’re done welding, the metal needs to cool down in order for the finished product to be strong and durable.
Argon prevents oxidation from happening during this process: it replaces oxygen in the atmosphere around your welds so that they don’t rust while they’re cooling down.
When using an argon-based shielding gas, it is important to ensure that there is enough flow rate through the torch and that you are using a high-quality argon cylinder.
The flow rate should be between 15 and 30 cubic feet per hour (cfh), depending on the size of the weld puddle being used. A minimum flow rate of 20 cfh is recommended for small puddles (1/2″ diameter or less).
Using Helium for TIG Welding
Helium is also inert gas and has a higher thermal conductivity. Using helium for TIG welding is a great way to ensure you get a clean, quality weld. I do not recommend 100% helium for manual TIG welding.
The helium shielding gas used in TIG welding helps prevent contamination of the weld pool by reducing oxidation of the filler metal.
Helium is lighter than air, so it rises and pushes out contaminated gases from around the weld area. This means that there’s less chance of contaminants getting into your weld pool and affecting its appearance or quality.
When using helium as a shielding gas for TIG welding, it’s important not to exceed its maximum allowable concentration level (MCL). If you do exceed this level, you’ll have problems with porosity or hydrogen embrittlement in your welds.
What Happens If I Use Hydrogen?
If you’re using hydrogen for TIG welding, you might be wondering what happens if you use too much.
The answer is that it could cause your weld to become brittle and break easily. That’s because hydrogen is a gas, and it doesn’t work as well as other gases when used for TIG welding.
If you want to avoid this problem, just make sure not to use more than 5% hydrogen in your tank. One more thing, I suggest only using hydrogen when TIG welding austenitic stainless steel or nickel alloys.
In the case of welding duplex stainless steel, it is better to use nitrogen with argon instead of using hydrogen.
Different Mixtures for TIG Welding Shielding Gas
1. Helium/ Argon:
The helium/argon blend is the most commonly used shielding gas for TIG welding. This blend allows for maximum penetration, making it ideal for welding thick materials such as steel and stainless steel.
The helium (75%) & argon (25%) blend also works well for welding aluminum, magnesium, and other nonferrous metals.
The helium/argon mix is often referred to as “medium-speed” because it produces less heat than pure argon but more heat than pure helium.
This makes the helium/argon mix suitable for applications involving thicker materials such as stainless steel or mild steel (1/8 inch or thicker), where a higher level of penetration is required.
2. Argon/ Hydrogen:
The argon/hydrogen mixture is a very popular shielding gas for TIG welding nickel alloys & austenitic stainless steel. It produces a bright, clean arc and can be used for welding and brazing.
The mixture contains 95% argon and 5% hydrogen, producing an arc that is easy to start but provides excellent heat transfer, allowing the metal to be welded efficiently.
The hydrogen in this mix helps prevent metal oxidation during welding. The oxygen content is low enough that it doesn’t interfere with the quality of welds produced by this shielding gas blend.
3. Argon/ Nitrogen:
It is a common shielding gas blend used with TIG welding with the argon (98%) & nitrogen (2%) blend.
It offers good arc stability and weld penetration but is better suited for use with higher-alloyed steels. This blend is often used for TIG welding duplex stainless steel, aluminum, magnesium, and copper alloys.
Gas Requirements for Different Metals
There are several different types of materials that can be welded using TIG welding, including steels like mild steel (both low-carbon and high-carbon), stainless steel, aluminum, tool steel, and nickel alloys.
The gas requirements will vary depending on what type of metal you’re working with. In this, I am going to guide you on which gas is best for different metals.
What Gas is Used for TIG Welding Aluminum?
A mixture of argon and helium is commonly used as a shielding gas when TIG welding aluminum because it reduces the amount of heat input required during welding, which helps prevent damage to the joint.
If you are using this type of shielding gas, you will need to add extra argon to compensate for the helium that escapes through leaks in your equipment or insufficient flow through your torch tip. You may also use 100% argon for this.
I recommend not using 100% helium for welding aluminum with AC TIG, but you may use it for DC TIG, but it is not good for beginners.
What Gas is Used for TIG Welding Stainless Steel?
When TIG welding stainless steel, you will need to use a mixture of argon and helium. The argon is used to prevent oxidation, and the helium helps to improve productivity.
The type of stainless steel you are using will determine your gas mixture. For example, if you are working with thin stainless steel, then I recommend avoiding mixing helium because it creates heat management issues.
If you want to weld thick stainless steel, then use 5% hydrogen with the argon. Whenever you want to weld duplex stainless steel, I recommend mixing nitrogen with argon instead of hydrogen.
What gas is used for TIG welding mild steel?
In order to get the best TIG welding results, it is recommended to use an argon/helium mix. This combination of gases provides better arc stability, superior penetration, and deeper amperage control than any single gas. In addition, it is safe on all metals that are welded with a TIG torch, including mild steel.
Other Metals:
If you aren’t sure what alloy of exotic metal you need or how it will be treated, I recommend using 100% argon.
You should use 100% helium with DC TIG for copper because copper vanishes heat quickly. For Chromoly metal, I recommend using 100% argon as shielding gas.
For nickel alloys, you should have to use 5% hydrogen, or you can use 100% argon or a mixture of argon/ helium.
Conclusion!
As you can see from the above article, argon is the most commonly used gas for TIG welding. Now you have an idea of what gas is used for TIG welding.
Argon is able to create consistent welds with little spatter and a smooth bead. Welding with argon allows the welder to be more confident in the quality and consistency of their welds.
In this, I have guided you in detail on how you can use different types of gas for TIG welding projects with the required gas blends. Best of luck with the TIG project!
FAQs:
Can I use CO2 for TIG welding?
CO2 is a consumable gas like argon and is not intended for TIG welding. CO2 can produce toxic fumes under certain conditions, so it is not advisable to use it as a TIG welding source.
Is TIG stronger than MIG?
TIG is stronger than MIG welding because it utilizes filler metals that have less porosity. The lack of porosity makes the welds much stronger and more durable than MIG welds.
Why is argon used in TIG welding?
Argon is the best shielding gas for TIG welding because it produces the lowest spatter and easiest cleanup. The lower energy burn rate of argon allows the arc to be drawn deeper into the weld zone, preventing damage to the base metal in thinner sections of work. Also, argon will form a stable arc between about 3/4” diameter electrodes and make a good quality weld without pulse control.
