Laser Marking Stainless Steel: Engraving, Etching or Annealing

Many types of stainless-steel alloys and grades exist. They're all made of elements such as iron, nickel, carbon, and chromium. The latter makes up for at least 10.5% of the alloy. Chromium reacts with oxygen and creates an isolating, thin layer that prevents the formation of rust on the surface.

Not all laser technologies can be used to mark stainless steel parts. For instance, you can’t laser engrave or laser etch stainless steel. To mark data matrix codes, barcodes, serial numbers, and logos, you must rather use laser annealing. This ensures that:

  • The mark will be permanent on the surface of the material
  • The metal surface will be left intact to avoid degradation by oxidation


This is especially true for applications like marking exhaust lines which are exposed to corrosive acids. It also applies to marking parts that must remain spotless like car interiors.

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Laser Marking with Fiber Lasers - A Stainless Reputation 

When it comes to stainless steel, some marking solutions aren't adapted to industrial applications. Methods such as inkjet printing require heavy maintenance and lead to frequent downtime. Those are examples of unplanned problems on the shop floor.

Laser annealing is a marking process optimized for stainless steel. When used with a fiber laser system, it offers unmatched advantages for your manufacturing process.

 

Permanent and 
Robust Marks

Real traceability is only possible by directly marking parts. Laser annealing does that by chemically modifying the steel under the part surface.

You will get permanent and high-contrast marks that can withstand high-temperature annealing and intense UV exposure.

Rust Resistant

Stainless steel must not rust after you've marked it. Even if it's naturally resistant to rust, removing its surface protection will expose the material to rust.

Unlike laser engraving, laser etching, and dot peening, laser annealing doesn't lead to rusting. This method only modifies the material under the part surface. It thus creates markings deep in the material while leaving the protective layer intact.

No Consumables

You can avoid managing consumables and regular maintenance while reducing your environmental footprint.

Unlike inkjet printing, fiber lasers don't use any consumables or contaminants. In addition, they require low maintenance, as there are no moving parts.

 

Interesting Facts About Our Laser Technology

When it comes to choosing a laser machine and a marking system for stainless steel, you typically don’t need a high power. To mark stainless steel, the laser must be pulsed at a lower energy than fiber laser engraving. Increasing the laser power could indeed damage the material.

Laser annealing is one of the only marking solutions for stainless steel. And although you can’t achieve the high speed of the engraving process, it creates a beautiful surface finish and offers a high precision (resolution of 200 microns).

 

What Happens to Stainless Steel When You Laser Mark It?

Laser annealing is a marking method that provides permanent markings without affecting the protective layer (such as chromium oxide) of certain metals like stainless steel.

If you want to know what happens to stainless steel when you laser mark it, read our post on why you shouldn't be laser engraving stainless steel to understand how our laser marking process works and why it's important.

Let Us Know Your Application

Let our experts know your stainless-steel marking application. They will guide you through the various types of laser products to choose a fiber laser system or machine that is just right for you. They can also work with you to optimize the marking speed for your application, and arrange tests using your parts to demonstrate the marking's quality.