Argon: What is it? And why is it used in welding?

What is Argon

Argon is a chemical element (Ar). It is the third most abundant gas in the atmosphere, which makes it largely available and therefore, relatively cheap. Argon is produced by distillation of liquid air. It is then put in gas bottles and sold. The argon gas is widely used in different welding techniques. The argon welding gas serves as a shield for the fresh weld of its surrounding atmosphere. This provides several benefits, making the welds more seamless and durable. We will talk more about that further down this article, but first, let us answer some of the most common questions about the Argon properties.

Q: What colour is argon?

A: Like many other gases with a dominant presence in the atmosphere, argon has no colour, nor scent.

Q: Is argon heavier than air?

A: Yes it is, almost 1.5 times heavier than air. It collects in low spots when being released in a facility.

Q: Is argon poisonous?

A: Argon is not toxic, but this does not mean it is not dangerous. Thanks to its density, and the fact it is hard to detect, it could harm individuals that find themselves in closed counters with a high concentration of argon in the air. Argon can lead to asphyxiation. Loss of consciousness followed by the stopping of the heart could happen in a matter of minutes. The only sign is a brief shortage of breath.

Q: Is argon flammable?

A: No, it is not! Argon is one of the laziest elements there is. It does not show any signs of its presence like taste, colour or smell. It is not flammable and it is not reacting with other elements.

Q: What does argon react with?

A: Nothing! Argon is an inert gas. It does not undergo chemical reactions under a set of given conditions. This is why is argon used for welding.

Argon in welding

We mentioned how the “laziness” of Argon is actually what makes it useful to us and the reason why is argon used in welding. Due to the lack of any reaction between argon and other elements. The inert gas serves a great purpose in shielding the atmosphere while welding. Argon is being dispersed straight through the tip of the welder, surrounding the arc and thus limiting the effect of moisture and other elements that otherwise may make the weld bridle, uneven or create spores in it. Sometimes the gas is being dispersed on the back of the weld as well to further protect it from the surroundings. This is the reason why is welding done in the atmosphere of argon. The noble gas is widely used in TIG and MIG welding. Other shielding gases as carbon dioxide, oxygen, nitrogen, and hydrogen are also used in different types of welding procedures. Combinations between different gases can give even better results for some scenarios. For instance, you would want a different shielding gas for welding steel and when welding aluminium. Companies are experimenting with the thickness of metals and different percentages of combinations between gases to establish some etalons. However, the technique of the welder will also play a role, so it is impossible to come up with a solution for all purposes.

Argon and CO2 is a popular combination, especially for welding thin sheets of steel. Pure argon solution is also available on the market, so are combinations between argon and oxygen.

Working with such gases, you must remember, that they can pose a serious threat to your health! Even argon which is neither flammable nor toxic. If the concentration in your surroundings gets high enough, it can push the air out of your lungs and lead to asphyxiation. Always make sure that you are wearing proper RPE’s and that there are proper welding extraction systems installed on the premises.