Answered on this page:
- What are the differences between laser engraving, etching and marking?
- When should I use laser engraving, laser etching, or laser marking?
- How do the methods and technologies differ for laser etching, engraving, and marking?
- What materials are best for laser engraving/etching/marking?
Etching vs Engraving
Have you ever wondered about the differences between laser etching, engraving, and marking? While all of these terms are vaguely similar, they all refer to completely different processes when it comes to using a laser to create markings, images, or designs in a chosen material. Laser etching, laser engraving, and laser marking are all unique applications of laser technology with their own distinct profile of requirements, risks, applications, benefits and characteristics.
With that said, it’s important to brush up on your terminology and understand the practical and technological benefits between these different laser applications – doing so will help you determine what type of laser configuration you should use for your next laser project. Below, we’ve created a list of our top-five differences that distinguish between these laser methodologies.
What is the Difference Between Laser Etching and Engraving?
Effect on Materials
Understanding how the laser process works and what effect lasers have on your chosen materials based on the methodology you use is the first step to seeing the differences between laser engraving, etching and marking. Each of these processes has a unique effect on the material to which it is applied.
Laser engraving makes a cone-shaped indentation in the surface of the material. Laser etching produces a high contrast marking on the surface of the material by vaporizing just the surface layer of the material. Laser marking creates high-contrast markings without disrupting the material itself using a method called discoloration.
Cut Depth
Under a microscope, it’s easy to distinguish between laser engraving, laser marking and laser etching work. Each of these laser methodologies correlates with a different range of cut depths for the laser.
Laser engraving removes more material and makes deeper cuts than both laser etching and laser marking. The cone-shaped indentations created in the laser engraving process can be deepened by passing the laser over the same areas several times. The maximum engraving depth depends on the chosen material, as laser engraving machines have a much easier time cutting through a soft material like graphite versus a metal like stainless steel. The maximum engraving depth for metals is typically around 0.020″, while for softer materials it could be around 0.125″ or 1/8 of an inch.
Laser etching makes much shallower cuts in the material, as the laser simply vaporizes the surface layer of the material. The total depth of laser etchings is typically no more than 0.001″ or one thousandth of an inch, and the material at the surface may melts and expands which leaves a raised etching rather than an indentation. Laser marking heats the material and causes the oxidation of sub-surface material which changes the color of the material and leaves a marking. This is done while leaving the surface intact, so the cut depth is essentially zero.
Laser Power
How do markers and engravers achieve different cut depths and effects using the same laser machines? Laser engraving machines are controlled by special software that allows the users to change the laser settings. Everything from the laser’s speed of movement to the number of passes the laser makes over the chosen material can be customized. To switch between laser engraving, etching and marking, laser experts change the power setting on the laser.
Laser engraving makes the deepest cut and actually vaporizes the material in its way. Effectively laser engraving requires the use of a high-heat laser, and engravers will often dial their laser’s power up to the maximum setting to get the best results, especially when using a robust material like anodized aluminum or stainless steel.
Laser etching also uses high heat to melt the surface of the material, producing a slightly raised etching pattern of your choosing.
Laser marking is achieved by moving a low-powered laser beam slowly across the surface of the material, discoloring the surface of the material and leaving the chosen mark. A low-powered laser generates just enough heat to oxidize the material under the surface and turn it black, creating distinct, high-contrast markings that are easy to identify.
Durability
Whether you’re creating an art project for sale or applying a legally required traceability marking to a jet propeller or a life-saving medical device, chances are that you want your laser markings to last for a long time. That’s just one of the reasons why it’s important to choose a laser marking methodology that matches your intended purpose.
Laser engraving is an ideal method for marking parts and items that are expected to experience high wear. If you laser etch a design into some jewelry, it will fade quickly if the piece is touched often because the depth is just 0.001 inches. Laser engraving’s deeper cuts are ideal for creating long-lasting markings on a variety of materials. Laser engraving is not recommended for safety-critical parts, as the engraving process can damage or structurally compromise the engraved part.
Laser etched markings are much less durable and mostly appropriate for surfaces that will encounter low levels of wear and tear.
Laser marking is the most common methodology for making traceability markings on medical devices or aerospace parts. This is because the laser marking process simply discolors the surface of the material without melting or vaporizing any of the material – it preserves the safety and integrity of the parts completely and creates long-lasting, high-contrast markings.
Versatility
Laser engraving, etching, and marking all have a variety of applications and can be used with many different materials.
Laser engraving is effective on almost any material of your choosing, including metals, plastics, wood, leather, acrylic, glass, and even soft materials like paper. Laser etching affects the surface of materials, altering reflectivity and enhancing contract. The best materials to use with laser etching are bare or anodized aluminum, plated metals, stainless steel, polymers and ceramics. Laser marking is used widely throughout industry to create permanent markings without destroying materials. Laser marking is used to create UID codes, QR codes, bar codes, and logos for a variety of products.
Summary
Laser engraving, etching, and laser marking are all common methods for creating permanent markings on a variety of materials, yet there are subtle differences between each of these methodologies that makers and manufacturers should be aware of, ensuring that they choose the best application for their needs.
Laser engraving creates a cone-shaped indentation in the chosen material using a high-powered laser. The cut depth is typically between 0.020″ and 0.125″, but deeper engravings can be achieved by passing the laser over the same area several times. Laser engraving is good for parts that experience wear and tear, but not parts that are critical for safety. Laser engraving is excellent for personalizing gifts and keepsake items, and can be used with a variety of materials.
Laser etching creates shallow markings of 0.001″ by using a high-powered laser to melt the surface layer of the chosen material. Laser etching is best for low-wear applications, as the shallow markings tend to fade easily over time. Hard materials like bare, anodized or plate metal surfaces are the best materials for use in laser etching applications.
Laser marking uses a low-powered and slow-moving laser beam to cause oxidation under the material surface, discoloring it and creating a high-contrast marking that is visible on the surface. Laser marking is commonly used to mark parts in the automotive and aerospace industries, as well as medical devices. Laser marks are long-lasting and don’t compromise the surface of the material when they are applied. Laser marking is used to tag products with UID codes, QR codes, bar codes, and other logos and images.
