Process Date: June 1999

Metal cutting with a laser is similar to many other cutting methods: a thermal source cuts the material with the assistance of a reactive gas. The advantage the laser has over other processes is the fineness and concentration of that source. A laser can be focused to diameters as small as 0.005", offering a number of benefits to the user:

 - High energy density, Minimal cut width, High cut resolution.

These factors make high speeds and intricate profiling of sheet steels possible. The resulting cut edges are square, with tens of microns roughness, and, depending upon material, little or no burring. The most suitable metals for CO2 laser cutting are hot and cold rolled mild steels, and austenitic stainless steels. It should noted that CO2 lasers with output powers less than 250 watts will not cut copper, aluminum, brass, silver or gold.

Two important energy thresholds exist for any material – the energy required to simply cut through the material, and the energy required to cut the material well. The table below shows the maximum thickness each power is capable of cutting.

Steel	25W	50W	125W	240W
Stainless	0.01"	0.016"	0.025"	0.08"
Mild	0.01"	0.016"	0.03"	0.16"

0.06" mild steel, cut with Synrad’s 60-2W, 240 watt laser at ~ 120 ipm