CO2 laser engraving machine is suitable for marking non-metallic materials

CO2 laser engraving machines are the go-to technology specifically for marking and processing a wide range of non-metallic materials. The suitability comes down to the laser’s specific wavelength and how it interacts with different materials.

The Science Behind It: Wavelength and Absorption

The key to understanding this lies in the CO2 laser’s wavelength, which is typically around 10,600 nanometers (nm) in the far-infrared part of the spectrum. 

 This long wavelength is very effectively absorbed by organic materials and materials that contain carbon. 

 When the material absorbs the laser’s energy, it heats up rapidly, allowing the laser to vaporize, etch, or cut it with high precision. 

Conversely, this long wavelength is the very reason CO2 lasers are generally unsuitable for marking bare metals. Most metals are highly reflective at this wavelength, meaning the laser beam bounces off the surface instead of being absorbed. 

Suitable Non-Metallic Materials

CO2 lasers excel at engraving and cutting a vast array of non-metallic substances.

Material Category	Examples	Performance Notes
Wood	Plywood, MDF, Balsa, Cork, Solid woods (Poplar, Birch, etc.)	Cuts and engraves very well. Engraving produces a natural, darkened contrast. Some woods and glues in plywood can cause more charring.
Plastics	Acrylic (PMMA), Delrin, Mylar	Acrylic is a very popular choice as it cuts cleanly and can produce a polished, “flame-finished” edge.  Note: Some plastics like PVC and polycarbonate should not be used as they release toxic fumes.
Textiles & Leather	Leather (natural and synthetic), Felt, Fabric, Cloth	Lasers can create intricate patterns on leather and can cut textiles while sealing the edges to prevent fraying.
Paper & Cardboard	Paper, Cardstock, Cardboard	Ideal for intricate cuts for invitations, stencils, and packaging. The process is fast and precise.
Glass, Stone & Ceramic	Glass, Marble, Granite, Tile, Brick	These materials can be etched but not typically cut. The laser creates a frosted effect on glass.
Other Materials	Rubber, Foam, Corian	Ideal for making rubber stamps, custom foam inserts, and engraving solid-surface countertops.

What About Metals?

While CO2 lasers cannot directly engrave bare metals, there are two important exceptions:

• Coated Metals: They work very well on anodized or painted metals, such as anodized aluminum. In this case, the laser is not engraving the metal itself but is precisely removing the surface coating to reveal the bare metal underneath.  
• Marking Agents: A special chemical spray or paste can be applied to a bare metal. The heat from the CO2 laser fuses the agent to the metal, leaving a permanent black mark.

For direct, high-speed engraving of metals like steel, aluminum, brass, and titanium, a Fiber Laser is the appropriate tool. Fiber lasers use a much shorter wavelength (typically around 1,060 nm) that is readily absorbed by metals, making them highly efficient for those applications.