Welding 101:Difference Between MIG and TIG Welding

Last updated on June 14th, 2023

If you are a beginner in the world of welding, then you might get confused between MIG and TIG welding.

I mean, honestly, both methods use an electric arc and shielding gas. Also, their names sound quite similar.

When faced with a choice between the welding techniques, it is understandable if you get overwhelmed.

So, to help you out, I decided to write an in-depth comparison of Tungsten Inert Gas (TIG) and Metal Inert Gas (MIG) welding.

In this article, I will be exploring the key differences and applications of both methods.

The knowledge will help you make an informed choice as you embark on your journey to become a successful welder.

Contents

The Art of MIG Welding – A Beginner’s Best Friend

Metal Inert Gas welding also known as Gas Metal Arc Welding (GMAW) is a versatile and popular welding method that is widely used all over the world.

The method is particularly popular among beginners because it is comparatively easy to learn and doesn’t require any special skill set.

The process uses a consumable wire electrode through a welding gun, which melts and fuses the base metal together. The feeding wire acts both as the wire electrode and the filler material.

MIG welding also uses shielding gas to protect the weld pool from any atmospheric contaminants.

Many professional welders are of the opinion that MIG welding has more advantages compared to any other welding method.

Some of the key advantages of this method are:

Ease of Use
Faster Learning Curve for Beginners
High Welding Speed and Productivity
Less Cleanup Required As Compared to Stick Welding
Versatile Application for Various Metals and Thicknesses
Fewer Instances of Weld Defects

The Art of TIG Welding: Precision At Its Finest

Tungsten Inert Gas (TIG) welding or Gas Tungsten Arc Welding (GTAW) is a highly precise welding technique that requires a high level of skill, control, and focus.

This welding method is preferred because of its high precision and finesse. It has the ability to create high-quality and aesthetically pleasing welds.

In TIG welding, a non-consumable tungsten electrode is used to generate the arc. The arc creates the necessary heat to melt the base metals and join them together.

You will have to feed the filler material externally if required. Yes, TIG welding is the only welding process that may choose not to use filler material.

TIG welding also uses a shielding gas that protects the weld area from atmospheric contamination and oxidation.

Various advantages make TIG welding a unique and distinctive method. Some of the prominent advantages are:

Exceptional Weld Quality and Precision
Versatile Method that can even be used on exotic metals.
Highly clean and aesthetically pleasing welds
Precise control of heat input
Better control of weld bead appearance

MIG vs TIG Welding: Head-to-Head Comparison

You might have understood the key difference between the two from the above brief descriptions. Let’s divide the in-depth comparison into three major parts, so you can understand it in a better way.

Part 1: The Differences in Consumables, Welding Process, and Results

There are some major differences between the two methods when it comes to the welding process, consumables, and results.

Let’s discuss them one by one.

The Wire Electrode

MIG welding uses a consumable wire feeder electrode that acts both as an electrode and as a filler material.

Spools are available in different sizes and capacities. You can choose the diameter of the wire based on a specific welding application.

Also, the wire feeder is the main controller of the welding process. Because it also acts as filler material, the welder can focus more on the project, making it an easy process.

You will have to use the wire of the same material as the base metal. Depending on the amperage, you will be able to weld with different welding techniques.

Increasing the wire feeder speed allows you to increase the productivity of the MIG welding process.

On the other hand, TIG welding uses a non-consumable tungsten electrode, which although precise and special, comes with its own limitations.

First of all, you will have to grind the electrode for specific welding requirements. Secondly, you will have to feed the filler material externally, which can be quite difficult to learn for a beginner in welding.

You will be using your both hands for different purposes and your non-dominant hand is not easy to tame.

Shielding Gas

The primary purpose of shielding gas in both of the welding methods is to protect your weld pool from any sort of atmospheric contaminants.

There are a lot of reactive gasses found naturally in the air that can contaminate your weld pool.

The shielding gasses used in both processes differ. You cannot use shielding gas for MIG welding in TIG, and vice versa.

MIG welding uses argon or a blend of argon with carbon dioxide for the welding process. The concentration of carbon dioxide in the blend will depend on specific welding applications.

CO2 is responsible for providing better penetration in the welding process.

On the other hand, TIG welding uses pure argon or inert gasses mostly. It cannot use CO2 because of the tungsten electrode. Tungsten is naturally sensitive to gasses like Co2 and oxygen.

So, you will have to use a blend of argon with helium, nitrogen, or hydrogen.

There is a technical aspect here. The active gasses used in MIG welding actually make the process MAG (Metal Active Gas) welding, but as the process is mostly similar, it is generally considered in MIG welding.

Another key difference between both methods is the flow rate of the shielding gas consumed during the welding process.

MIG welding typically uses 35-50 cubic feet per hour (CFPH) while TIG welding only uses 15 to 25 CFPH.

Weld Strength and Durability

Although MIG welding is more popular and widely used, TIG welds are generally considered stronger.

TIG welding is a precise process that is better at creating strong and durable welds. The process uses a precise and focused arc that is more accurate and penetrates the metal in a better way.

Adding to this, TIG welders are known for producing clean and strong welds which do not have any defects, holes, or spatter.

However, that does not mean in any way that MIG welds are weaker. A MIG welder is also known for creating strong and durable welds.

In my opinion, it depends on the welder and the welding technique. A good welder can create perfect and durable welds with either method.

Welding Speed

One of the key factors where MIG and TIG welding hugely differs from one another is the welding speed.

MIG welders offer much faster speed as compared to TIG welding. That is the reason MIG welders are known for their high-volume production and productivity.

In the process of MIG welding, the electrode acts as the filler material which means the filler wire is being constantly fed to the weld pool which increases the speed of the weld.

The weld pool or puddle will move much faster, and you will be able to get the task done in much less time.

However, in the case of TIG welding, you simply cannot move as fast. TIG welding is a precise endeavor that tolls a heavy cost in the form of low speed.

But professionals consider the clean and good-looking welds worth the patience and extra time.

Skill Level—The Learning Curve

MIG welding is considered a pretty straightforward process, which means it is comparatively easier to learn.

There are not many intricacies or complexities involved in the MIG welding process. You can fine-tune your way to perfection.

The biggest advantage is that the filler material is automatically fed to the machine, which allows you to focus more on speed and other aspects.

MIG welding is versatile and is also able to handle more thickness. You can use the welding gun with only one hand.

However, in the case of TIG welding, it is not so simple. You require a high level of skill and extreme focus for the welding process. So, there is a steep learning curve.

Two things make TIG welding more difficult to learn. Firstly, you will have to feed the filler material externally with your non-dominant hand at the same time you are using the torch with your dominant hand.

Taming the non-dominant hand for such a precise endeavor can be quite difficult.

Secondly, TIG welding involves precise control of heat input, which is usually controlled through a foot pedal.

Learning to use this foot pedal can take quite some time, as you will have to build perfect coordination between your hands and feet.

That is why MIG welding is considered less complicated and much easier to learn.

Welding Aesthetics

Despite the high productivity, ease of learning, and challenging strength of MIG welding, one thing it can never beat TIG welding is the welding aesthetics.

TIG welders can create clean and professional welds that are visually pleasing to the eyes. There is a rare chance of a spatter, and you may require light polishing after you finish the welding process.

The process produces neatly stacked dimes that are aesthetically pleasing when done on joints that are not polished or coated.

But in no way does that mean that MIG welds are ugly. Professional MIG welders can create good quality MIG welds but in terms of looks, they won’t be as aesthetically pleasing.

Since, most of the time, welding is done on raw metals which are later polished, painted, or coated, so looks do not matter that much in general application.

However, for the process where looks do matter, TIG welding takes the trophy.

Part 2: Difference in Applications

Both TIG and MIG welding are used in a wide range of applications including various industries and manufacturing projects.

MIG welding is generally used in:

Automotive and Transportation
Construction and infrastructure
Manufacturing and fabrication
Maintenance and repair work

Similarly, TIG welding also has various applications:

Aerospace and aviation
Precision equipment manufacturing
Food and beverage industry (for sanitary welds)
Artistic and decorative metalwork

These were just to mention a few. Instead of focusing on these details, let’s discuss where in their application process they differ.

MIG welding is more suitable when you have to weld thicker metal sheets or bigger pieces. The continuous wire feeding makes it more productive as compared to the TIG torch and external wire feeding.
On the other hand, TIG welding is better for thinner materials because it doesn’t let the metal sheet burn out or warp because of its ability to produce precise and clean welds.
MIG welding has high volume production, which means it can be used in the long run and can withstand continuous usage. However, TIG welding requires many breaks to make adjustments.
However, when you are dealing with short runs like welding a pipe joint, TIG welding works best.
MIG welding is more suitable for beginners and less-experienced welders. It doesn’t have much of a learning curve. However, you cannot allow beginners to work with TIG welders.
MIG welding allows you to get into difficult positions and weld beads easily since you only have to use one hand. As for TIG, welding joints in difficult positions is limited and the process is mostly used for workbench applications.
MIG welding is a preferred choice where high production is required, especially of steel and aluminum. It can create more beads at a much faster speed which increases productivity.
TIG welding can be used for various metals including stainless steel, aluminum, and other exotic metals, but only when you are dealing with shorter welds and low-volume production.
MIG welds require cleaning and polishing afterward to make them look cleaner, but they are still widely used in all industries because the material will be painted afterward.
TIG welding has more application for artwork, automotive restoration, and other places where the weld beads would be visible and aesthetics matter more.

Part 3: Difference in Weldable Metals

While most metals can be welded using both methods without any extra technicalities, there are two specific metals that pose special challenges in both welding methods.

Stainless Steel

Stainless Steel retains heat efficiently, unlike mild steel or carbon steel. So, when you are welding this metal, there are high chances of warping and distortion.

MIG welding stainless steel is tricky, especially when it comes to choosing shielding gas.

You cannot use pure inert gas and or pure active gas, so you will have to go with a blend. But the dual gas blends also don’t give you the best results.

So, welding stainless steel with MIG welding will pose certain challenges. Using Tri-Mix gas blends is the solution but getting their concentration right takes a bit of fine-tuning.

Compared to this, TIG welding is much more efficient for this metal. The foot pedal provides accurate heat control to the welder that allows him to prevent warping or distortion.

Adding to this, TIG welding is a highly precise welding process with a very focused arc which will ensure that there are no welding defects.

However, despite this, MIG welding is preferred because it gives high-volume production and is still a comparatively easy process.

Aluminum

Welding aluminum poses challenges for both welding methods. The layer of oxides on the surface of the base metal has double the melting point of the metal itself, which will present a serious challenge.

TIG welding aluminum requires the use of Alternating Current (AC) which means you have to get a TIG welder that comes with AC compatibility. TIG welders with AC control are more expensive.

MIG welding aluminum is comparatively easy. You will have to use aluminum feed wire but the process itself is not very difficult. Just like stainless steel, there are some technicalities involved with the shielding gas.

However, that doesn’t mean you won’t face any issues while MIG welding aluminum. You can run into all sorts of problems like bird nesting or wire tangles in the spool because of the nature of aluminum.

Also, you will have to use a fresh, clean, and dry aluminum spool for wire feeding.

So, welding aluminum is challenging. If you are not careful, you might impact the corrosion-resistant ability of the metal or produce a weaker weld.

Exotic Metals

Because of the delicate and expensive nature of these metals, TIG welding is preferred with them.

TIG welders are able to create clean and precise welds, without any spatter and with aesthetically pleasing visuals.

MIG welding can also be used for welding exotic metals, but the welding machine will require tweaking and the welder will require a massive skill set and years of experience.

Cost—A Decisive Differentiator

Cost is one of the biggest differentiators between the MIG and TIG welding process.

TIG welding is an expensive process as it is slow and takes a lot of time. TIG welders are experienced and have special skills, which means they charge higher per hour.

Such welding machines are also expensive, and the consumables cost a lot. So, overall, TIG welding is a very costly process.

On the other hand, MIG welding usually costs very less. You have the advantage of faster welding speed and also it requires less skill and preparation. So, the overall costs will be much lower.

Frequently Asked Questions

Why is MIG welding better than TIG?

MIG welding is comparatively easier to learn, costs less, and also has high productivity which makes it better on some level. However, TIG welding is more precise and has delicate applications where it produces aesthetically cleaning welds.

What is the difference between TIG and MIG aluminum welding?

Aluminum TIG welding requires AC compatibility as you cannot weld using DC polarity. However, in MIG welding, you only have to change the shielding gas and the polarity has no effect.

Which is hotter, MIG or TIG?

Both processes use an electric arc, which means their heat is beyond the charts. However, MIG welding beads cool down much faster, so in a way, TIG welders can be considered hotter.

Is TIG stronger than MIG?

Generally, TIG welds are considered stronger than MIG welds because of their precise and accurate nature. However, an experienced MIG welder also produces durable and strong weld beads.

Is MIG or TIG better for steel?

For mild steel, MIG is more suitable as it can provide higher productivity. However, when it comes to stainless steel, both methods present certain challenges. MIG is generally preferred, but some professionals choose TIG over MIG welding.

What is the strongest weld?

TIG welding is considered the strongest welding technique because it produces a very precise and focused arc. The welds created by an experienced TIG welder are considered the strongest.

Which gas is used in MIG welding?

Various gasses are used in MIG welding. You can use pure argon, CO2, helium, blends of gasses, and also trimix gasses. Argon-CO2 mixture is the most widely used shielding gas in MIG welding.

Wrapping Up!

To sum it all up, both MIG and TIG welding are versatile processes with various applications in a diverse range of industries.

Each method comes with its own set of pros and cons. The above article discusses each aspect of them in detail.

MIG is generally preferred over TIG because of two major reasons. MIG has higher productivity and comparatively less cost.

However, TIG welding also has its own application in specific areas where it cannot be replaced with MIG welding. TIG has the looks, the strength, and the hygiene which MIG can never match. But it also charges a heavy amount for these delicacies.

Despite all this, one method cannot be termed superior to the other. It all depends on the specific welding application to choose which one would suit best.

Still, got some questions? Drop them in the comments section below and I will get back to you as soon as I can. Happy Welding!

Author
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Sheila James

Editor at Weld Empire

An accomplished welding expert known for her impeccable welds and innovative contributions. Sheila prioritizes safety and sets industry standards. As a passionate educator, she guides and inspires the next generation of welders to excel.