Plasma cutting is one of the fastest, most efficient ways to cut metals such as carbon steel, stainless steel and aluminium, allowing you to cut through materials up to 6 inches thick.
However, to achieve a superior clean cut, you need to make sure you are using the right type of gas for your material. There are several gases that are used in plasma cutting, with each one having its own advantages and disadvantages. Find out below which gases are used in plasma cutting, plus what gas you should use for each type of metal.
Compressed air
Air is one of the most adaptable forms of gas on offer, and as you don’t have to purchase it, this dramatically lowers the cost of the overall cutting process. That being said, shop air is a superior choice as it is cleaned before sold, thus eliminating contaminants such as oil, mist and moisture.
For cutting aluminium:
- High-quality cuts
- Good speed
- Cost-effective
For cutting carbon steel:
- Adequate speed
- Cost-effective
- Precise cut
For cutting stainless steel:
- Moderate cutting speed
- High-quality cut
Oxygen
If you want fast speeds with lower power levels when using your plasma cutting machines, then oxygen is the plasma gas for you. Ideal for cutting structura- low carbon and low alloy steel, it can be used for cutting materials with a variety of different thicknesses.
For cutting aluminium:
- Not recommended
For cutting carbon steel:
- Excellent cut quality
- Little to no dross
For cutting stainless steel:
- Not recommended
Nitrogen
If you need to cut large amounts of aluminium or stainless steel, then nitrogen is a great choice. This plasma gas offers excellent parts life but is not the best option for thick materials.
For cutting aluminium:
- Highly recommended
- High-quality cut
For cutting carbon steel:
- Great parts life
- Fair quality cut
For cutting stainless steel:
- Good cut quality
Hydrogen
Hydrogen plasma gas is classed as environmentally friendly as it reduces the emission of Co2. This gas contributes to increased productivity due to its high-speed cutting.
For cutting aluminium:
- High-quality cut
- Great parts life
For cutting carbon steel:
- Good quality cut
- Excellent parts life
- Some dross
For cutting stainless steel:
- Excellent cut
- Excellent parts life
Argon
For materials that are greater than ½ an inch thick, argon is good to use. Argon does not react with metals when cutting, which is why it is classified as an inert gas.
For aluminium cutting:
- High-quality cut
- Ideal for thick materials
For carbon steel cutting:
- Not recommended
For stainless steel cutting:
- Excellent cut quality
- Ideal for thick materials
Argon-Hydrogen
You can also use an argon hydrogen mix to cut through stainless steel and aluminium. This is usually a percentage of 35 hydrogen and 65 argon. This option offers maximum cutting capacities and is the hottest plasma gas available.
It should be used for any cutting processes that involve materials that exceed a 3 inches thickness.
Plasma Gas
As well as the five named plasma gases above, plasma gas can also be further categorised into three different phases:
- Ignition gas that is used to light the arc and commence the metal cutting process
- Cutting gas that determines the cutting speed and the cutting finish
- Marking gas that is used for plasma marking
Need help picking the right case for your plasma cutters? Get in touch with our friendly and knowledgeable team here.
