No matter how advanced we’ve become, what latest technology we use, there are a few things that remain the same for years and decades — using assist gas in laser cutting. But why is that so important?
Fiber laser cutting is an efficient method that offers various precise cuts from automotive to aerospace engineering. In order to bring out quality and accuracy, assist gas plays an important role in fiber laser cutting.
Their presence during laser cutting guarantees superior results than you’ll expect. Understanding their importance and role is essential for making out the best from laser cutting processes.
What is Assist Gas in Laser Cutting?
Laser cutting assist gas is used along with the laser beam during cutting. This makes the cut speed faster and improves the quality of the cut. Assist gas mainly removes the molten material and debris from the cut zone. It blows away the molten material so it doesn’t stick back to the surface and cools the material to stop it from changing shapes.
Compressed air, oxygen, and nitrogen are commonly assist gases in laser cutting. This can be selected depending on the material and the outcome expected.
Assist gas offers exact, clean cuts while impacting quality, speed, and the end product suitable for processes. As fiber laser technology is evolving, understanding the use of assist gasses helps in improvement and innovation.
Assist Gas in Laser Cutting
When using a laser cutting machine, especially a fiber laser cutting machine, the choice of gas is important as it affects both the cut quality and the efficiency of the process. This can lead to a lot of benefits in terms of production quality and cost savings.
Let’s see a few types of assist gas used in fiber laser cutting.
- Oxygen
Proper choice of gas is important in assist gas laser cutting for clean and precise edges, and so oxygen is one among them. You can use oxygen to cut hard materials like carbon and mild steel as it helps in burning the metal.
Oxygen is commonly used because it is a highly reactive gas that causes an exothermic reaction. This increases the power of the laser beam, allowing thicker materials to be cut. Oxygen reacts with the material that is being cut while creating a chemical reaction that helps melt and vaporize the material. As a result, it produces a clean, oxide-free cut.
But oxygen can cause oxidation, which creates a rougher edge and gives a poor product finish, requiring additional finishing processes.
- Nitrogen
The most commonly used assist gas in laser cutting is nitrogen. Mostly stainless steel and laser cutting aluminium are the materials that get cut with nitrogen. It’s an inert gas that prevents oxidation during the process of cutting. It offers a perfect and shiny cut by eliminating oxygen in the air, preventing it from reacting with hot sheet metal.
Nitrogen is best for higher productivity as it helps increase cutting speeds and lowers cost. This results in a cleaner and smoother cut. Although nitrogen gives better results, generally it is more expensive than oxygen and comparatively slower in cutting.
- Compressed Air
Compressed air is a cost-effective option. You can cut non-metallic materials like plastics, wood, and acrylics with compressed air. It provides a balance of decent cutting speed and minimized edge oxidation as the air is composed of about 78% nitrogen and 21% oxygen.
It gives a cooling effect and helps to remove debris from the cutting area. The advantage of using compressed air is it readily available in maximum quantity and so the cost of getting it is very low.
But due to 21% of oxygen, it is not ideal for cutting thick or critical parts and sometimes might lead to slight oxidation.
- Argon
Argon is an inert gas commonly used for laser cutting applications and materials that require a high level of precision. It leads to extremely clean cuts and is used for cutting materials that are thin. It also prevents oxidation and produces high-quality edges.
Argon can be used similarly to nitrogen but it is more expensive and so reserved for high-quality requirements.
- Helium
There are situations where helium is used as assist gas in laser cutting. This is especially done for applications that require very high energy density or to cut thick materials. This gas is used because of its heat transfer properties that help to achieve faster cutting speeds and improved cut quality. Helium gas is also more expensive and is generally used for high-quality requirements.
How to Get The Most of Assist Gas in Laser Cutting?
You need to consider a few things to get the most out of assist gases.
- Choose the Right Gas
Different gases have different properties and react differently with various materials. Therefore, we need to consider the composition of material, thickness, and the cut quality before choosing the gas.
- Adjust Gas Settings
We need to consider the flow rate and pressure of the gas. If the flow is too low, it may not work properly, while if it is too high, it can cause too much turbulence or blowout. Therefore, it is best to try different settings to find the best balance.
- Choose the right Nozzle
Choosing the right nozzle size helps you cut faster and more accurately. Make sure the nozzle is aligned with the laser beam—if it’s off, the gas won’t flow evenly, and the cut quality can drop. Also, check and clean the nozzle often to avoid blockages or damage that could affect gas flow.
- Maintain the Supply Clean
The assist gas supply should be clean and free from contaminants. If not, it can lead to poor cuts and low efficiency. Inspect clean the gas supply system including the filters and nozzles to avoid any issues.
- Experiment with Different Settings
Experiment with different gas settings, flow rates, and pressures. This is because the optimal settings for assist gases can vary depending on the material, thickness, and desired outcome.
Conclusion
Choosing the right assist gas in laser cutting depends on different factors including type, thickness, cut quality, and other considerations like cost. Every gas has its own pros and cons. So it’s better to analyze before selecting them.
To know more about assist gases and which one will suit your tasks, it’s better to contact professionals. You can explore Cesar CNC to find a range of fiber laser cutting and welding machines. Precision, speed, and quality!
