Choosing the Right Assist Gas for Laser Cutting: Nitrogen and Beyond

Laser cutting is a process where metals, such as stainless steel, carbon steel or aluminum are cut with a high-powered laser beam.  Assist gas, or the gas that is used to aid the cutting process, is essential to the performance of the laser.  Choosing which assist gas should be used is based on three specific items:

1. The specific type of material being cut
2. The required edge quality
3. The material’s thickness

Nitrogen is the most common assist gas used when no discoloring is the requirement (so the cut must be excellent).  The laser cutting process vaporizes the metal, and the nitrogen gas moves the vaporized metal away from the cut edge before it re-solidifies (since the cut edge is heated, it will bond with oxygen if present). Creating a barrier between the heated metal edge and the atmospheric oxygen also eliminates or reduces discoloration of the cut edge. This assist gas also aids in the dissipation of heat, helping the edge cool faster.

After determining that nitrogen would be best for your application, the next step is to size the amount of nitrogen needed.  Specifications that are required are the following:

1. Annual CCF delivered (100 CCF is 100 cubic feet)
2. Annual nitrogen spend
3. Hours of laser operation
4. Nitrogen pressure
5. Metal types and thickness (assists in fine tuning the design and system proposal)

Interested in utilizing nitrogen gas in your laser cutting application? Reach out to Atlas Copco! Our industrial gases experts will be happy to assist!