Laser Marking: What It Is and How It Works

Laser markings are everywhere—showing up on common household appliances, automotive parts, medical and surgical equipment—the list goes on.

With innovations in technology, the use of lasers for marking and engraving has become an industry standard for companies needing a way to permanently transfer information on parts and products.

So, what exactly is laser marking and how does it work? In this article, we’re going to explore some of the basics of laser marking and its use.

What Is Laser Marking?

When parts need a permanent label, such as a serial number or a specification list, laser marking is often used. It’s a process that uses a laser beam to heat up the surface of a material in order to leave a permanent mark or reading. Laser marking encompasses a wide variety of applications such as annealing, engraving, etching, carbon migration, and discoloration.

How Laser Marking Works

A laser, in its essence, is a concentration of atoms stimulated to release particles of light. The word laser literally stands for—Light Amplification by the Stimulated Emission of Radiation. When a laser focuses on something, this concentration of light heats up particles of the material it comes in contact with.

By using this focused beam of light, laser marking alters the appearance of the material it comes in contact with. Because a laser is very precise, it can create very small and accurate markings. Industries use laser marking on almost any material—glass, plastic, metals, wood, etc.

Laser Marking Applications

Annealing is the process of changing the color appearance of a material by heating it up. The heat creates an oxidation reaction that leaves a permanent mark—this process removes no material.

Laser engraving removes material from a surface and is used on almost any material, including metal. This metal laser engraver, for example, makes engravings that usually go to a depth of .001 to .005 inches. Similar to laser engraving, etching is a shallower removal of material with a depth of .001 inches or less.

Carbon migration is a process used on metals and alloys. When the metals are heated with a laser, it creates a chemical bond with carbons, creating a permanent near-black mark. Because this process only affects the surface, this type of laser marking is typically used on medical equipment where smooth surfaces are desired.

Discoloration is a process used exclusively for plastics. The heat from a laser changes the coloration of the material, usually creating a slightly raised surface. The coloring varies depending on the material.

Part Identification & Traceability for Every Industry

Laser marking for part identification and traceability is used in every industry. How the marking process is performed will depend on the size of your part, its finished, curvature, material, and post-processing requirements.

Did you find this article about laser marking useful? Check out our other tech’ articles in our blog section for more fun and interesting topics.