English
Created on 07.16
What are assist gases in laser cutting?
Assist gases are used in laser cutting to improve the quality and efficiency of the cutting process. The assist gas helps to blow away the molten material and prevent it from re-solidifying on the surface of the material. It also helps to cool the material and prevent it from warping or distorting. The most commonly used assist gases in laser cutting are nitrogen, oxygen, and compressed air.
1. Use of nitrogen in laser cutting
Nitrogen is the most widely used assist gas in laser cutting, thanks to its inert properties. It is used to ensure a high-quality performance of the laser, particularly when a high-quality cut is required. Nitrogen eliminates oxygen in the air and thus prevents it from reacting with the hot metal, resulting in a perfect, shiny cut, without affecting the color of the material (this will depend on the purity of nitrogen used). Nitrogen gas, being inert, keeps the cut edge from oxidizing by enabling the laser to run in an oxygen-free environment. Nitrogen is also essential for lower cost, higher cutting speed, higher productivity, better control, highest efficiency, on-demand nitrogen, and a plug-and-play solution.
2. Use of oxygen in laser cutting
Oxygen is used in laser cutting to cut materials that are difficult to cut using other methods. Oxygen is a highly reactive gas and causes an exothermic reaction by multiplying the power of the laser beam, allowing thicker materials to be cut. Oxygen reacts with the material being cut, creating a chemical reaction that helps to melt and vaporize the material. Depending on the material, oxygen is also used to increase the cutting speed and reduce the cost of the cutting process. However, oxygen can cause oxidation, which can cause a carbon layer to form on the cut edge, resulting in poor product finish and adhesion problems for any coating or paint applied to the oxidized surface. Due to the high reactivity of oxygen, very thin slices cannot be obtained.
3. Use of compressed air in laser cutting
Compressed air can also be used as an assist gas in laser cutting and can be faster and more cost-effective for laser cutting. However, it does not allow to obtain parts with very clean cuts because air has 21% oxygen in its composition (normally, these parts need be deburred before the next process, which takes some extra labor). These cuts are valid in parts that are later going to be painted or welded, in which the color of the cutting edge does not matter.
The purity of the assist gas will depend on the customer's requirements for the final product, although we must consider that:
If we use atmospheric air the purity of the air cannot be changed, we will have 78% nitrogen and around 21% oxygen.
If we use oxygen, we're generally going to have purities above 99.5%.
And if we use nitrogen, it will depend on the material to be cut, whether the material is going to be treated afterwards, the importance of the color of the cutting edge, etc.
Bearing in mind that, by decreasing the purity of the nitrogen, we will reduce the cost significantly.
For product or sales enquiries please contact：
Shanghai A-Turbo Energy Technology Co., Ltd
Tel: +86 13816886438
Email: zhu@a-turbocn.com
Website: www.a-turbocn.com
Contact
Leave your information and we will contact you.