Welding is a trying task, and a layman will probably not understand all the science behind it. It is also a dangerous and risky occupation, though one that has a lot of career scope. Welders usually go through different certifications and hands-on training at welding school and apprenticeships to fully become capable of performing it themselves.
If you think welding is hard work, TIG welding is far more difficult. Ever seen a welder standing on one leg, complete with all the safety equipment, for hours, trying to join pieces together? TIG welding is hard work, but the result is as satisfying as the work is hard. The appearance and quality of the welds are, by far, the best that are produced – no matter what kind of welding is taken into consideration.
A lot of confusion exists when it comes to the difference between different kinds of welding. And that’s okay because the technical details about each type are difficult for a layperson to understand, but here, we attempt to clear it up for you a bit.
There are three main welding types:
- TIG Welding: Also called Gas tungsten Arc Welding (GTAW), TIG welding utilizes a tungsten electrode that gives current to the welding arc. The tungsten and the weld pool are protected by an inert gas mixture.
- MIG welding: Gas Metal Arc Welding (GMAW) is another name for this form of welding. MIG welding has a metal wire that is heated and melted to create an arc of electricity. This arc melts and joins the work pieces together.
- Stick Welding: Stick welding is the informal name for Shielded Metal Arc Welding (SMAW), where a consumable electrode covered with flux is used to melt the metal work piece and join the pieces together.
There are other types of welding, too, but these are the most common ones out there. For this article, we are going to study TIG welding, what it is, how it works, and why it is the best type of weld there is.
What is TIG Welding?
The two terms (tungsten inert gas welding and gas tungsten arc welding) are one and the same and can be used interchangeably. TIG welding gained popularity because of its ability to weld aluminum and magnesium with such perfection, but it can weld all other sorts of metals too, including copper, copper alloys, and stainless steel. Not only is it capable of welding all metals, but it also does it with great precision and neatness, making the resultant welds of extremely high quality and purity.
TIG welding creates an electric arc when the tungsten electrode and the base metal come close to each other. Tungsten or a tungsten alloy (with other elements and oxides) is chosen as a non-consumable electrode because tungsten has the highest melting point of any metal, i.e., 3,410 degrees Celsius.
While TIG welding has transformed the welding world and has replaced gas and manual metal arc welding that were traditionally the only option before, it is also the reason aluminum is widely used to build industrial structures now. TIG welding is used extensively across many industries, but it is also the most complicated welding technique yet. It can only be performed by experienced welders and require proper training.
Applications of the TIG Weld
TIG welding is compatible with many different metals, and thus, can be used for almost all kinds of jobs and repairs across all industries. TIG welds are also very strong and durable, making them perfect for industrial welds. TIG welding is very common in industries like aerospace, repairs, automotive, and fixtures, and metal sculptors.
- Aerospace – Airplanes and space equipment needs to be made of the strongest possible materials, and they should be constructed with the utmost precision and accuracy, making TIG the appropriate option for such construction projects. Known for the strong and precise welds that TIG creates, the aerospace industry utilizes the technique a lot. The International Space Station has also had TIG welding done.
- Automotive – It is essential to make strong automobiles that can last years and do break down as a result of regular wear and tear. TIG welding is thus the perfect technique to use in these situations. TIG welds make the car safer and more durable for travel, and even helps reduce rust in the car’s body.
- Repair – TIG is a good technique to use in repair tasks, as it helps make the repaired piece last longer. TIG techniques are used in the repair of automobiles, aluminum tools, and all sorts of other things.
- Art – One of the major reasons why TIG welding is preferred is because of its neat appearance. In art pieces or decorative fixtures and structures, appearance is of utmost importance, so TIG welding is chosen for artwork and decorative pieces as well.
When to Use TIG Welds
Keeping the properties of TIG welds in mind, we can say that TIG welding is perfect for use in situations and projects where:
- The welds need to be very strong
- The weld beads need to be aesthetically appealing and good-looking
- The metal that needs to be welded is thin
How to TIG Weld
Though TIG welding can only be learned and perfected through experience and practice, here are the basic steps to follow when welding using a tungsten inert gas.
Choose the Electrode
Choosing the right electrode is of the utmost importance. While the name suggests that the electrode has to be tungsten, you need to decide whether to get a pure tungsten electrode or a tungsten alloy. Some of the common, approved alloys include:
Cerium oxide, also known as ceria, is an alloying agent that is believed to develop arc stability. It is non-radioactive.
Another non-radioactive alloy that improves arc stability and performance is that of lanthanum oxide, or lanthana.
Touted to be ideal for general purpose use, thorium oxide (also called thoria) gives good arc performance. However, it is radioactive and can pose some health hazards.
Improved arc stability and increased electrode life are the benefits of using zirconium oxide (or zirconia) in your electrodes. This helps you cut down on electrode replacement costs.
Grind the Electrode
Once you have decided on the material of the electrode, you need to decide whether to ball the tungsten or sharpen it to a point. A pointed tip gives a more stable arc, but whether you should grind the electrode to either one of these depends on the material you are welding and the type of current you will be using.
Insert the Electrode in the Collet
Place the prepared electrode into the electrode holder.
Adjust the Settings
TIG rigs typically have three main electricity options – AC, DCEP, and DCEN, which should be chosen and adjusted according to your requirements and needs.
- AC is for aluminum – choose “AC.”
- DCEP means “DC, Electrode Positive.” This setting is used to ball the tungsten tip, or for stick welding.
- DCEN means “DC, Electrode Negative,” and is used to weld steel.
Turn on the Gas
Typically, pure argon gas or a mixture of argon and helium or carbon dioxide is used to protect the tungsten electrode from wearing away. Tungsten reaches incredibly high temperatures, and if there is nothing to protect it, it will rust or corrode away very quickly. Inert gases are used for this purpose because they do not react with anything, even at such high temperatures. The gases you use also vary according to the metal you are working with.
- For aluminum, you can use pure argon.
- For steel, you would use an argon and carbon dioxide mixture.
Prepare welding and Welding Table
You can buy a dedicated welding table for the job, or you can place a large, flat metal sheet and start working. This is necessary to get the electricity to flow through your metal. If you want the welds to turn out very strong and good-looking, wipe down the table and electrodes with acetone.
Wear Safety Clothing
Once everything is ready, don on your safety clothing. Wear a safety suit, welding gloves, and darkening helmet to protect yourself from the glare, sparks, and hot metal.
Once your work station is prepared, hold the electrode an inch away from the metal and jam down on the pedal, adjusting the current flow as you go.
TIG and MIG: A Comparison
If you can’t tell the difference between tungsten inert gas and metal inert gas, you are not the only one. Many people get confused between the two, and the similar-sounding names don’t help much either. Tungsten Inert Gas and Metal Inert Gas welding are two different welding techniques that employ different operating mechanisms and are used for different situations and metals. Here, we give a general comparison between the two on different fronts to clear up the confusion between TIG and MIG welding.
While both processes yield high-quality results, TIG welds are of a far more superior quality. They are neat and aesthetically better than MIG welds.
Tungsten inert gas welding requires a non-consumable tungsten electrode with argon or a mixture of argon and helium mixture of gases to create an arc, while metal inert gas welding has a solid wire being fed into a weld pool to join the pieces together.
MIG welds are relatively cheaper than TIG welding because TIG welding takes more skill and precision than MIG.
Not much experience in welding is required to perform a MIG weld. MIG welds are simpler and can be done by a beginner level welder, while TIGs are usually performed by experienced welders.
TIG welds take more time when compared to MIG welding.
TIG Welding: Advantages and Disadvantages
While all welders will tell you that TIG welds are the best there are because of their high-quality results and their adaptability to all sorts of metals, there are certain drawbacks to TIG welds too. What works best in one situation might not work in other situations. It is best to know the drawbacks and benefits of TIG welding so you can make an informed decision the next time you have to opt for what type of welding to use in your project. Listed below are some of the most common advantages and challenges associated with TIG welding.
- TIG welding yields a very neat result and is used in situations where very precise welding work is required. The cosmetic appearance of the weld is better in TIG welds than in MIG welds.
- TIG welding is compatible with a variety of different metals.
- TIG welds are of superior quality; they are stronger, durable, and give high-purity welds, while other types of welds are not of the same quality.
- The equipment required for TIG welds is pretty affordable, making the service reasonably priced.
- While TIG welding produces strong welds, you have to make sure you are working with a clean metal as impurities and contamination can result in weaker welds.
- The process of TIG welding has a low deposition rate; it can only be done at a certain pace and cannot be rushed through.
- While all welding should only be done when you have a certain level of education and awareness about the welding process, TIG welding especially is not child’s play. Out of all other types of welding, TIG requires the most skill, dexterity, and nimbleness. The welder often has three out of four limbs occupied while performing a TIG weld!
- TIG welding requires skill and dexterity, and only an experienced welder can effectively perform it. This is why the labor costs for TIG welding tend to be higher, despite the equipment not being expensive.
- Since the TIG weld is strong and durable, pieces that have been TIG welded are very hard to pick apart. It is possible, and a professional welder can manage, but it often leaves the pieces damaged and unsuitable for further use.
Now that you know everything under the sun about TIG welding, you should have a better understanding of whether it is the right choice for you. Whether you are trying to learn TIG welding, deciding if TIG welding is better for your project, or you want to make a career out of it, the information covers pretty much everything that you should know about TIG welding. Happy welding!
Can you weld without gas?
Without a shielding gas, you will burn the tungsten, as it can reach very high temperatures and rust or corrode away. It will also cause the weld to be contaminated and won’t get any penetration into the work piece.
Can any gas be used to TIG weld?
No, only inert gases can be used. Argon is the main shielding gas used for TIG Welding and for MIG and Aluminum welding. CO2 produces a cooler, coarser arc, and a marginally harder weld. The other gas commonly used is helium. A mixture of helium and argon is usually preferred.
What is the ideal temperature for TIG welding?
In TIG welding, the properties of the tungsten metal allow it to maintain an arc temperature of almost 11,000 degrees Fahrenheit. A high melting point and excellent electrical conductivity keep the tungsten electrode from burning up!
What is more preferable, TIG, or MIG?
TIG welds are very neat and precise, so if the work piece needs to be aesthetically pleasing, a TIG weld would be more preferable. TIG welds are also better if you plan to work with thinner gauge materials. With thicker metals, MIG welds are a better option as it is considerably faster than a TIG weld.
When was the TIG welding technique invented and perfected?
Russell Meredith, who was a part of Northrop Aircraft, first invented and perfected this process in 1941. He named the process “Heliarc,” as it used helium as a shielding gas and a tungsten electrode arc.