The Differences Between Laser Engraving, Laser Marking, and Laser Etching

Each laser process has its place and each can be used as a permanent solution for compliance to regulations for marking and coding parts and products. What sets laser engraving, laser marking, and laser etching apart?

The Differences in Laser Processes

The terms laser engraving, laser marking, and laser etching are all used interchangeably, but there are differences between the three processes. Each one has its own process, attributes, and applications that make it the right one for the jobs. Here is an overview of the different laser processes.

Laser Engraving

The laser engraving process involves the laser beam removing the surface of the material that results in a cavity that creates an image seen at eye level.

• The high heat from the laser beam essentially vaporizes the material.
• The process is very fast as the material gets vaporized with every pulse of the beam.
• The cavity produced via laser engraving is obvious to the eyes and to the touch.
• To get deeper engraving marks, the process is repeated through several passes over the material.

Laser engraving is a subcategory of the wider category of laser marking, though it does have its differences.

• There are three types of laser engraving – deep laser engraving, laser ablation, and etching. The difference relates to the surface and how much is removed.
• This process is most commonly used for having something customized or personalized, but is also used for parts that often undergo high wear.
• Laser engraving can engrave logos, serial numbers, and the like on various materials such as wood, plastic, metal, glass, leather, and others.

Laser engraving is faster, causes less damage to materials, can be used on several types of materials, is more legible than conventional engraving, and it has more options for fonts.

Laser Marking

Laser marking occurs when the beam engages with a surface, slightly changing the appearance of properties of it.

• A low-powered bean slowly moves across a material, using a discoloration technique, creating high-contrast marking without digging into the material.
• Oxidation occurs under the surface as the laser engages the surface, causing the material to blacken.
• The surface remains intact as the low temperature process anneals the surface.

Laser marking is less common and is used for charring metals and plastics. Laser marking has four types: carbon migration, annealing, coloration, and foaming. It’s most used in the medical industry for marking titanium and stainless steel. It can also be used on other materials for bar codes, logos, UID codes and other identification codes.

Laser Etching

Laser etching melts the surface of the material upon which it is used.

• A high-heat laser beam melts the material’s surface.
• The melted surface expands, resulting in a raised mark.
• The depth is not as deep as engraving.
• Laser etching is used on plated, anodized, or bare metal and ceramics and polymers.

In all the processes the laser beam has a focal point on the material so it creates the desired effect for whichever process is appropriate. All these laser processes are used across a variety of industries.

Laser etching, engraving, and marking has increased in popularity over the past several years, mostly due to all the government and industrial rules, laws, and regulations that require products to be clearly labeled and/or identified.

Article contributed by Needham Coding