The short answer is yes, stainless steel can be laser engraved. It is a misconception that engraving is never suitable for stainless steel. Feasibility will depend on the application, environment and available laser engraving equipment.
The process of laser engraving stainless steel involves the physical removal of the surface layer of the metal by an intense laser beam to create the engraving of the desired design.
A method called deep is also commonly used to mark stainless steel. It is similar to engraving, but the material is processed multiple times. This means calibrating your machine to emit relatively low power at slower speeds, then repeating the process multiple times. When using this process on stainless steel, more material is removed to produce a cleaner engraved design.
What is the best way to mark stainless steel?
When deciding to laser engrave stainless steel, there are several ways to go about it. CO2 lasers can engrave pretreated stainless steel, or fiber lasers can engrave or etch stainless steel. Stainless steel is also suitable for laser annealing.
Deep laser engraving is often used to mark stainless steel. In order to obtain deeper engraving, the marking speed of the laser needs to be reduced, and the power needs to be increased. After multiple passes through the stainless steel at different angles, a clean design will result.
Another way to mark stainless steel is to anneal it. Annealing is a less invasive type of laser marking. Annealing is characterized by low power applications for extended periods of time. When you anneal stainless steel, you melt it, but you don’t remove any material. This means that the chromium oxide layer remains intact and continues to prevent stainless steel from rusting or corroding.
By annealing stainless steel, you expose it to relatively low heat for extended periods of time. This process melts the material or substrate without removing the layers that protect it from oxidation or rust.
What kind of laser is needed to engrave stainless steel?
Fiber laser engravers are ideal for engraving stainless steel. A CO2 laser can also be used, but a marking solution must be applied to the surface beforehand. Many laser engraving contractors offer two laser options to achieve the customer’s desired look.
Let’s take a closer look at these two laser engraving techniques and how they perform on stainless steel.
A CO2 laser is a gas laser. Its core usually uses carbon dioxide or helium-neon gas. The older of the two methods, CO2 laser engraving is still commonly used, but operates less efficiently than fiber lasers.
CO2 laser cutters can engrave wood, plastic and metal, including stainless steel. However, CO2 lasers cannot directly engrave metal because the laser beam reflects off the surface. In order to engrave stainless steel, the material must first be pretreated with a marking solution such as CerMark or LaserBond.
This engraving style is ideal for light surface etching, including engraving stainless steel jewelry and other personalised items, as well as plaques and trophies.
Fiber laser machines are the latest development in the industry and are more efficient than CO2 lasers. Today, this is the preferred option for engraving or marking stainless steel.
Fiber lasers are more stable and very precise than CO2 lasers. Its power ranges from 4kW to 15kW or even 20kW, well above the threshold for CO2 lasers. For this reason, fiber lasers are more commonly used in industrial applications and large production runs where efficiency and speed are critical.