Stainless steel is an iron alloy that contains carbon and at least 10.5% chromium. The chromium forms an oxide layer that protects the iron from rusting. Alternative names for stainless steel are corrosion resistant steel and CRES. The stainless steel surface can be marked with either a CO₂ laser or a fiber laser. In each case, the laser beam energy causes the oxide to darken, creating a bold laser mark. Fiber laser marks are darker than marks created by CO₂ lasers because the fiber laser wavelength is absorbed more efficiently by the stainless steel. A fiber laser is also capable of laser cutting thin stainless steel (up to about 0.005 inches or 125 microns).

• Laser Processing Guide for Stainless Steel