Stainless steel and aluminum require a separate application review from carbon steel. An oxygen-containing blend may affect oxidation, color, weldability, coating preparation, burr, dross, and safety. Do not transfer a carbon-steel gas ratio or parameter set to a non-ferrous job without approval from the machine and process owners.
Start with the part specification
If the drawing, customer standard, welding procedure, food-contact requirement, or machine documentation prohibits oxygen or requires a defined edge condition, use an approved process that satisfies that requirement.
Evaluating Stainless Steel
Pure nitrogen is commonly used when an inert assist gas supports the specified bright, low-oxidation edge. A mixed-gas trial should be considered only where the specification permits an oxygen fraction and the resulting edge can be qualified.
For each stainless grade and thickness, record the laser, optics, nozzle, pressure, flow, ratio, focus, speed, piercing strategy, edge color, oxidation, roughness, burr, dimensional tolerance, finishing work, and downstream welding or coating result.
Evaluating Aluminum
Aluminum processing has material- and machine-specific safety requirements. Follow the laser manufacturer's approved assist-gas guidance, extraction requirements, parameter limits, and site risk controls before testing any oxygen-containing blend.
Where a trial is permitted, use representative parts and document burn-through, dross, edge roughness, dimensional tolerance, corner behavior, rejects, and finishing work. Approval on one alloy, temper, thickness, or geometry does not establish approval for another.
Trial Matrix
| Input | What to hold constant | What to measure |
|---|---|---|
| Material | Grade, temper, thickness, batch | Edge, dross, heat tint, rejects |
| Machine | Laser, optics, nozzle, focus strategy | Complete cycle and stability |
| Gas | Source quality, pressure, flow, ratio | N₂ and O₂ per accepted part |
| Part | Geometry, piercing, corners, nest | Tolerance and finishing time |
| Downstream | Welding, coating, appearance criteria | Process-owner acceptance |
Ratio-Control Requirements
Before selecting a gas mixer for laser cutting, confirm its ratio range, control accuracy, repeatability, calibration method, pressure and flow limits, alarms, traceability, preset handling, and changeover procedure. A published ratio is only a test reference when the complete process condition is also stated.
Mixed Gas vs Compressed Air
Compare compressed air and mixed gas under the same part-acceptance standard. Include compressor, dryer, filtration, dew point, oil and particle controls, electricity, maintenance, gas cost, cycle time, rejects, finishing, and any contamination controls required by the laser manufacturer.
Decision Rule
Use a mixed-gas process only after the machine compatibility review is complete, the material and safety requirements permit it, representative parts pass the acceptance criteria, and the total-cost model uses measured local inputs.
Review a Non-Ferrous Application
Send the laser model, material grade, temper, thickness range, current gas, edge requirements, and downstream process. We can identify the compatibility and trial inputs that need confirmation.
Review Compatibility Inputs →