Fiber laser marking machines are versatile tools used for engraving, etching, and marking various materials. The color of the marking depends on the material being processed, laser settings, and surface interactions. Here are the common colors achievable with fiber laser marking:
1. Common Colors on Metals
Black Marking – Achieved through oxidation or annealing on stainless steel, titanium, and some alloys. Common for high-contrast engravings.
White/Gray Marking – Produced by micro-surface changes on stainless steel, aluminum, or anodized surfaces.
Gold/Yellow Marking – Possible on titanium or through controlled oxidation on stainless steel.
Dark Brown/Reddish Tones – Seen on copper or brass due to controlled oxidation.
Rainbow Effects – On titanium or stainless steel by adjusting laser parameters to create thin-film interference colors.
2. Colors on Plastics & Polymers
Black or Dark Gray – Common on dark plastics due to carbonization.
White/Light Gray – Achieved on light-colored plastics by foaming the surface.
Other Colors – Some engineered plastics can produce green, red, or yellow marks based on chemical additives.
3. Factors Affecting Marking Color
Laser Power & Speed – Lower power/slower speed may darken metals, while higher speeds create lighter marks.
Frequency (Pulse Width) – Adjusting frequency can change oxidation levels, affecting color.
Material Composition – Alloys, coatings, and surface treatments influence color outcomes.
Gas Environment – Using nitrogen or argon can prevent oxidation, leading to brighter marks.
4. Special Techniques for Color Marking
Annealing Marking (for stainless steel/titanium) – Produces colors without material removal.
Laser-Induced Oxidation – Generates darker or colored marks on metals.
Engraving Depth Control – Deeper engravings appear darker due to light absorption.
