How to Laser Engrave Copper?

Laser engraving copper uses a process called sublimation. Sublimation is the action of a material moving from the solid to gas state without moving through the liquid state. This allows a laser to easily vaporize a layer of material in order to create contrast or depth and form a fully permanent mark on the material without the concern of the copper becoming malleable and losing form.

When laser engraving copper, different styles of marks can be achieved, each requiring varying intensity, power, and speed. Fine-tuning these laser parameters is a vital step in creating an aesthetically pleasing mark, as the same laser that can produce significant depth when programmed to engrave can also be delicate enough to create surface-level interactions to create light and/or dark marks without changing the depth much at all.

Additionally, copper is highly reflective, so laser engraving copper with a laser that either won’t be reflected back or can do multiple passes is essential.

With all of this in mind, the best laser for engraving copper is a UV laser. Copper absorbs UV laser light instead of reflecting it so that the laser won’t need multiple passes for a high-contrast engraving. UV lasers also use a “cold marking” method ideal for heat-sensitive materials like copper. “Cold marking” uses absorption rates so high that it doesn’t put any heat onto copper, so it doesn’t risk conductivity.

Fiber lasers often face challenges when marking copper surfaces due to their reflective nature. The high reflectivity causes a significant portion of the laser energy to bounce off the surface, resulting in ineffective marking.

However, the introduction of hybrid lasers has proven to be a game-changer in this regard. With their high peak power, hybrid lasers can deliver intense bursts of energy, allowing for better absorption by the copper material. This increased absorption ensures that a smaller portion of the hybrid laser's energy is lost to surface reflection, making them much more effective at marking copper and other reflective materials.

Copper’s high reflectivity and thermal conductivity demand wavelengths that couple efficiently, with UV (355 nm) enabling “cold” marking and crisp contrast on thin or plated parts. Hybrid high peak power IR is effective when deeper engraving or tougher alloys are involved, while conventional IR often needs more passes and reflection control. Stable fixturing, clean surfaces, tight focus, and tuned scan strategies (overlap and hatch) drive repeatability. In production, integrated vision and 3 axis control maintain placement and focus across curved or stepped geometries and can grade codes to ISO/IEC 15415. KEYENCE systems combine these capabilities to help engineers achieve consistent, low HAZ copper marks without excessive iteration.

Copper and copper alloys are frequently used for jewelry, trophies, decorative plates, and ornaments because of their malleability, color, and anti-corrosive nature. Laser engraving copper is a way for people to hold onto mementos and customize gifts for loved ones. The clean engraving from lasers is aesthetically pleasing, permanent, and perfect for display.

Choose the engraving mode to match the requirement:

• Dark oxide contrast for speed and readability
• Bright mark for clean appearance
• Deep engraving for post process survivability

Copper can be separated by precision ablation for foils and thin stock or by thermal cutting for thicker sheet, with process choice driven by thickness, edge quality needs, and allowable heat affected zone. UV ablation or short pulse IR yields burr minimal edges on foils. Short pulses, controlled repetition rates, and optimized pierce/lead in reduce dross and redeposition; on axis vision verifies kerf before subsequent passes. Lasers excel for microfeatures, tight internal radii, and fast design changes; heavy busbars may still favor mechanical methods with lasers reserved for serials and reliefs. KEYENCE platforms add vision alignment and 3 axis beam control to keep kerf and feature location consistent across lots.

The future of copper is bright but a bit daunting. As the world moves away from fossil fuels and commits to electric energy, the demand for copper is rising fast. S&P Global predicts that copper demand will double by 2035, but S&P Global and governments fear miners won’t keep up and copper will significantly increase in price.

With that being said, that is all the more reason to switch to laser engraving copper or laser etching copper now, as it can greatly reduce scrap and prevent counterfeiting. If copper prices go up, the demand for laser engraving will also increase. Especially since laser engraving machines are also environmentally friendly, it goes hand-in-hand with future copper initiatives.

Don’t wait for laser engraving copper to surge. Even if you’ve never used a laser marking machine before, there’s always time to learn.

At KEYENCE, we’re passionate about assisting you. Our knowledge team specializes in setting you up with your perfect laser by answering any of your questions and offering demos. Get your hands on a laser now—contact us today!