Laser materials · Stainless steel
Laser engraving stainless steel
Fiber lasers mark bare stainless steel directly. Diode and CO₂ lasers need help from a marking spray. Which route you take decides what results are possible.
Which laser for stainless steel?
| Laser | On bare stainless |
|---|---|
| Fiber | Marks directly: dark annealed marks, bright etches and, with slow passes, deeper engraving |
| MOPA fiber | All of the above, plus colour marking by controlling heat with pulse width and frequency |
| Blue diode | Needs a laser marking spray or paste; the laser bonds it to the steel as a permanent black mark |
| CO₂ | Needs a marking spray or paste; most of the beam is reflected by bare metal |
| UV | Fine surface marks |
With a fiber laser
A fiber laser can produce a few different kinds of mark depending on power, speed, frequency and line spacing. Slow, low-frequency passes heat the surface and create a dark annealed mark under the surface, good for tools and serial numbers. Faster passes etch a lighter mark. Many slow passes remove material for a deep engraving. Around 40 kHz is a common starting frequency; slow down for a deeper mark.
Colour marking with MOPA
MOPA fiber lasers can turn stainless steel blue, gold, purple and other colours by growing an oxide layer of controlled thickness. The colour depends on many settings at once, so the reliable way to find them is a test grid. The Color Hunt studio in the app sweeps any two settings across a labelled grid; you click the square closest to the colour you want, refine around it, and save the recipe. It is free to use.
With a diode or CO₂ laser
Spray or brush a thin, even coat of laser marking compound onto clean steel and let it dry. The laser fuses it to the surface as a permanent black mark; wash the rest off with water. Even coverage matters: thin patches give grey marks, thick patches can flake. It works on tumblers, flasks, knives and tags, and on other metals such as brass.
Clean first. Degrease with isopropyl alcohol. Oil and fingerprints cause patchy marks with every method.
Cleaning up
Wipe the residue off after marking. Annealed fiber marks are under the surface and won’t wipe away; marking spray residue washes off with water and a soft brush.
Safety
Metal reflects laser light, so eye protection rated for your laser’s wavelength is essential on any open machine, and fiber lasers at 1064 nm need goggles rated for that wavelength specifically. Vent the fumes from marking sprays as you would any other job.
Related materials and settings
If you are new to metal, anodized aluminum is the easy starting point: almost any laser marks it without spray. Starting values for stainless steel on fiber and with marking spray are on the xTool settings page and the other brand pages. Confirm with a test card.
xTool is a trademark of its owner. Laser Generator Studio is an independent product and is not affiliated with or endorsed by it.