When cutting thin gauge material there s not much need for additional speed.
Laser cutting mild steel with nitrogen.
If the steel is thicker than 1 8 in cutting speed is similar for both nitrogen and oxygen.
If you are cutting stainless steel or aluminium this is usually only cut with nitrogen or compressed air compressed air is typically used to laser cut material up to 2mm thick.
Nitrogen or oxygen can be used as the assist gas.
Also if your cutting mild steel that has mill scale.
Nitrogen laser cutting is suitable for shaping mild steel although other factors affect the decision.
When cutting stainless steel or carbon steel with nitrogen the laser melts the steel and the nitrogen assist gas evacuates the molten material leaving an oxide free edge.
Meeting your nitrogen purity challenges the nitrogen purity is important if a clean cut edge is required for example when cutting stainless steel or aluminium metals.
However there are two choices when cutting mild steel.
I have a 160 w chinese laser that i would like to cut mainly 1 2 mm mild steel 1 2 mm stainless steel and up to 1 6 mm hr steel.
When carbon steel is cut with an oxygen assist gas the oxygen interacts with the hot metal to create an exothermic reaction which adds heat.
However if the laser cuts too fast turns a sharp corner or its focus is a little off you risk losing the cut and producing unusable parts.
Laser cut sheet with a nitrogen assist gas and you get a clean edge.
At our shop we nitrogen cut 7ga p o at speeds of about 70 80ipm on ext and around 60ipm on internal.
Higher figures are possible with the most powerful lasers available.
Cutting mild steel.
We have found how fast you can push depends on the material when we get higher carbon material.
Using nitrogen provides the most benefit when you are cutting very thin material.
The following show 12 6 and 3 2 mm 1 2 1 4 and 10ga mild steel cut with oxygen on a 2kw fiber laser and examples of the same part cut with 1 variable changed to show how it affected the cut quality.
The examples of the adjustments made will be similar for any co2 or fiber laser cutting mild steel with o2.
For mild steel and stainless steel thick sheets the ideal pressure lies in the region between 10 and 15 bar.
On amada fo3015 nt and 4020nt lasers.
When using nitrogen an inert gas the cutting process relies solely on the beam s energy to melt the metal.
With nitrogen as an assist gas can you advise starting settings pressure power and speed.
Speed at times is reduced for a clean cut by 20.
Cut the same sheet with oxygen assist gas and you get a rougher edge that needs clean up but thanks to the additional heat produced you can cut much faster.
