Laser marking is a broad term for any process that uses a focused laser beam to create a permanent mark on a surface. From engraving deep logos into metal to adding delicate traceability codes on plastics, different methods offer unique advantages. Understanding the main types of laser marking is the first step toward finding the perfect solution for your project.
Unfortunately, there's no single "best" laser for every job. The ideal choice depends on your material, desired mark type, and production speed. This guide will explore the three most common laser marking processes—engraving, annealing, and etching—to help you make an informed decision.
Laser Engraving: Creating Depth and Durability
Laser engraving is a popular method that uses a high-powered laser to vaporize material from the surface, creating a visible and tactile indentation. The resulting mark is permanent and highly resistant to abrasion. The three primary types of lasers used for engraving are UV, Fiber, and CO2, each excelling with different materials.
UV Lasers: The "Cold Marking" Solution
UV laser engraving operates on a principle known as “cold marking.” It uses a high-energy, short-wavelength (355 nm) ultraviolet beam that breaks molecular bonds in the material without generating significant heat. This prevents burning, melting, or heat stress, making it ideal for delicate and heat-sensitive materials.
When to Choose a UV Laser: UV lasers are unmatched in their versatility. They can mark heat-resistant materials with precision while also safely marking sensitive ones like plastic and glass. Their biggest advantage is their ability to create high-contrast marks on highly reflective metals like gold, silver, and copper, where other lasers struggle.
Fiber Lasers: Power and Speed for Metals
Fiber lasers get their name from the fiber optic cable used to amplify the laser beam to a powerful 1090 nm wavelength. This process results in extremely high output power, making fiber lasers the industry standard for marking and engraving hard materials, especially metals.
When to Choose a Fiber Laser: If you need deep, high-contrast marks on metal, a fiber laser is your best choice. The depth achieved makes the marks incredibly durable, capable of withstanding harsh environments, painting, and even corrosion. Its high power also translates to faster marking speeds, making it perfect for high-volume production lines. However, this intensity can damage heat-sensitive materials.