Search
Close this search box.

What Is Laser Marking?

What Is Laser Marking

What Is Laser Marking?

Laser marking is a laser technology that produces permanent marks on a wide range of materials. Current industry regulations require parts to be clearly and legibly marked, thus increasing the reach of the laser marking process. Previous industry trends required manufacturers to use traditional engraving or screen printing processes to mark surfaces. These processes are non-permanent, expensive, and often result in part defects.
However, the introduction of laser marking now enables engineers and manufacturers to create numbers, images, or characters without compromising part quality. Instead of using a physical tool to etch a surface, laser marking uses a focused laser beam to create an easy-to-read, damage-free mark. Laser marking is a process with a wide range of uses. Laser marking is a general term that can be interchanged with different processes, such as ablation, engraving, foaming, coloring, carbonization, etc., and the selection method depends on the material and quality requirements.
Table of Contents
Laser Marking

What Is Laser Marking?

Laser marking technology uses a focused laser beam to imprint text, numbers, logos, or patterns on any surface. A laser beam is emitted by an oscillator and scanned using a mirror (called a scan mirror), then a focusing lens is used to focus the beam on the target and mark it by changing the surface. Since laser marking involves using the laser to alter the target surface, this method is more wear-resistant than ink-based, and the markings will not fade over time.
In short, laser marking is a permanent process that typically uses a fiber laser, CO2 laser, or UV laser to create a durable mark on a surface. The most common types of laser marking applications are:
  • Annealing
  • Carbon migration
  • Discoloration
  • Engraving
  • Etching
Laser marking can be used in conjunction with automated equipment to achieve high-speed processing. Laser marking can leave permanent traceable marks on various materials such as steel, titanium, aluminum, copper, ceramics, plastics, glass, wood, paper, and cardboard. Parts and products can be marked with text (including serial and part numbers) and machine-readable data (such as barcodes, unique ID codes, and 2D data matrix codes).
How Does Laser Marking Work

How Does Laser Marking Work?

Laser marking technology creates durable marks on workpiece surfaces by generating a focused laser beam containing high power. Mirrors are used to release the accumulated energy into a coherent beam directed at the surface of the material.
As the beam interacts with the surface of the part, thermal energy is transferred from the beam to the surface. As a result, the appearance and properties of the material change. Depending on the energy level, lasers can very precisely engrave, etch, anneal, or discolor surfaces.
Focusing the beam to target only specific areas on the material enables laser marking machines to create precise, high-contrast, and high-quality marks on virtually any surface. These marks are permanent and you can easily read or scan them on any surface. Therefore, this labeling process is well-suited for operations where persistence and accuracy are critical.
Types of Laser Marking Technology

Types of Laser Marking Technology

There are various laser marking technologies suitable for different applications. Each technique has its advantages and disadvantages, and your choice will depend on budget, quality requirements, and application. Let’s take a look at some of these techniques together.

Laser Engraving

The laser engraving process involves using a laser beam to melt and evaporate some material from the surface of the workpiece. During this process, the material absorbs the heat of the laser, is then melted and vaporized, and finally forms the mark in the form of a depression. Plus, the material reacts with air, causing a color change that makes the mark even more unique.
Because there are no consumables involved in the laser engraving process, it has lower operating costs than other engraving methods that use special inks or drills. Lasers work on a wide variety of materials, including metals, plastics, and ceramics, so engineers can use them for many different applications.

Annealing

Anneal marking is a special type of laser etching of metals. During this process, a laser beam locally heats the metal surface to create a mark. The laser beam penetrates only 20 to 30 µm into the surface of the material, so surface changes are minimal. Localized heating causes the material to change color, and depending on the temperature of the heated layer, the markings can be black, red, yellow, or green.
The result of laser annealing is a permanent wear-resistant mark. Laser annealing works best on ferrous metals and titanium, and will work poorly on non-ferrous metals and aluminum because their color is not affected by heat and oxides.

Laser Etching

This highly versatile process melts the workpiece surface to form markings on workpieces, such as serial numbers, data matrix codes, logos, and barcodes. Laser beams create raised marks by delivering a large amount of energy to a small localized area. As a result, the surface melts and expands, changing the color to black, gray, or white. It is also a versatile laser marking process suitable for a variety of metals, including aluminum, steel, magnesium, stainless steel, and more.

Carbonization

Carbonization can create a strong contrast on bright surfaces. During carbonization, the heat generated by the laser heats the surface of the material (minimum 100°C) and releases oxygen, hydrogen, or a mixture of the two gases. Wherever this reaction occurs, it leaves a dark region with a higher concentration of carbon.
Since the marks formed are gray to blue-gray, carbonization is not always suitable for dark objects. This will result in a lower contrast between the marked portion and the rest of the workpiece. In general, carbonization is used to mark wood, paper, leather, packaging materials, etc.

Foaming

Carbonization may not be of much help when producing lighter-colored markings, but foaming is better suited for such applications. The foaming process involves applying a laser to heat the surface of the material, causing it to melt and release air bubbles. When the bubbles oxidize, a type of foam is formed and reflects light.
This method is one of the best markup options for dark components. This is because the markings are raised above the surface of the component, providing a higher contrast with the rest of the surface. It is also ideal for labeling polymers.

Remove

This laser marking method is particularly suitable for coated materials. During this process, the laser beam removes the topcoat applied to the workpiece to expose the underlying layer (substrate). If the two layers have different colors, a contrast will be created. Common materials that are lasered by removing the surface of the material include anodized aluminum, coated metals, foils, and laminates.

Discoloration

Sometimes the chemical composition of a material can give us an advantage when laser marking. The laser beam locally heats the material, and this heating triggers chemical changes. If the by-products are of different colors, they provide high contrast wherever the laser makes contact with the surface.
Penetration is not required for discoloration, and marking depends on the thickness of the oxide layer. Typically, the color change method is used for marking plastics, as the result of localized heating of the plastic is the deposition of soot on the material. It gives the appearance of dark marks on the surface.
Types of Laser Marking Machines

Types of Laser Marking Machines

Many types of laser marking machines can be used for different applications, each of which has its advantages and disadvantages, and which one to choose depends on the application, budget, and quality requirements. Here we will discuss the two most common laser marking machines used for marking: CO2 laser marking machine, and fiber laser marking machine.

CO2 Laser Marking Machine

The CO2 laser marking machine is suitable for CO2 gas as the laser medium, which is the most suitable system for marking organic materials. CO2 lasers can also be used on metals to make permanent, high-contrast marks if the metal has been treated with a special marking agent.
CO2 lasers have the longest wavelength (10600nm) of all laser marking systems, which makes them useful for marking different materials required by different industries, such as paper, wood, and some plastic polymers. CO2 laser marking machines can create permanent serial numbers, logos, and barcodes on electrical appliances, integrated circuits, food and medical packaging, and electronic components.

Fiber Laser Marking Machine

Fiber laser marking technology is becoming more and more popular these days because these laser marking machines are some of the most powerful laser marking machines available today. The solid-state lasers, which operate at power levels ranging from 20 to 100 watts, stimulate rare earth metal ytterbium production. This metallic element can generate photons with a wavelength of about 1,090 nm, making it ideal for marking metallic materials.
Fiber laser marking machines are suitable for deep engraving or etching. They give better results on harder metals, or when you need a higher-powered system with a smaller spot size for higher resolution. Due to the small spot size, high beam quality, and larger lens, these markers are ideal for batch marking small components.
Fiber laser marking machines are less expensive to buy than other machines, and the system is reliable. It even marks difficult-to-mark materials such as PCBs, plastics, nickel, and gold plating. Fiber lasers are best suited for laser etching using annealing, engraving, and marking processes on plastics. It has a service life of at least 25,000 hours. Also, MOPA lasers are a special type of fiber laser. MOPA lasers are extremely versatile, as the pulse duration can be modified to process large volumes of materials.
What Are The Benefits of Using a Laser Marking Machine

What Are The Benefits of Using a Laser Marking Machine?

Advances in marketing technology have opened the eyes of project managers to the need to brand their products. As a result, laser marking has now become an essential part of the manufacturing process. It helps businesses track their products, minimize counterfeiting, improve quality, and more. Laser marking machines can help you make precise markings with high precision, saving you time and money. To help you understand the enormous potential of this tagging technique, keep in mind the following benefits:

Marking Speed Is Fast

Laser marking combines laser technology with computer technology to ensure faster and less time-consuming implementation. Laser marking technology allows you to create designs on a computer and uses the latest graphic design techniques. This results in high productivity and cost-effectiveness in the manufacturing process. Depending on the material structure and size, different laser sources such as fiber lasers can be used to further increase the speed.
Traditional labeling methods use specific tools, making the process time-consuming. Laser marking machines, on the other hand, only need one command to get the job done in a short time. This is the perfect choice to shorten product development cycles, speed up the process, and save you a lot of money.

Environmental Marking Process

Marking processes such as chemical etching and inkjet use chemicals and inks to mark. Consumables for this process are often expensive and release harmful gases back into the environment, which can have a negative impact. However, laser marking is not suitable for any consumables, so it is a clean, energy-saving, and environmentally friendly process.
In addition, laser marking technology is a non-contact process that ensures clean processing and limits material contamination. Other types of marking systems may burn away material, but laser marking is non-destructive and involves little material penetration.

Compatible With Most Materials

There are a variety of laser marking machines on the market, each of which can work on various materials. For example, CO2 laser marking machines can provide the best marking effect on organic materials such as paper, wood, and some plastic polymers. Similarly, fiber laser marking can be used for marking various metals, such as steel, aluminum alloy, stainless steel, etc.

Consistent Repeatability

Laser marking machines can be successfully used to mark high volumes of products with fixed designs in large-scale manufacturing settings. This marking technology makes it easy to integrate identical markings into production lines. Additionally, this repeatability is consistent and will allow for faster turnaround and better-looking products.

Marking Durability

Laser-created marks are usually permanent and have high-contrast properties. These water and fade-resistant markers can withstand abrasion, heat, and acid. Therefore, laser marking is the choice of long-lasting marking necessary for product tracking, and you don’t have to worry about the marking fading.
Like dot peen systems, laser marking technology creates durable marks in harsh conditions such as chemicals. Therefore, parts manufacturing industries such as automotive and aerospace favor its use for its permanent marking. Permanent and durable markings allow these manufacturers to track and identify their products regardless of the field lens used.

Low Maintenance Process

Laser marking is a non-contact technology, so there is no mechanical wear between the laser marking system and the workpiece, which ensures that maintenance and downtime are kept to a minimum. Apart from the electricity cost of the equipment, laser marking machines have almost no daily operating costs. You need very little maintenance to remove the accumulated dust from the mirrors you use.

Summarize

Laser marking is a versatile marking technology that encompasses a wide range of techniques to produce precise, permanent, and high-quality marks. This environmentally friendly marking technology is an excellent alternative to traditional marking techniques, ensuring high production speeds, consistent repeatability, durable marking, and low maintenance. Therefore, laser marking is the best choice for your application.
When your product needs a high-quality laser marking effect, please contact AccTek, and let us help you get started! AccTek focuses on expertise and application of laser marking solutions. We offer laser marking machines ranging from 200 watts to 100 watts and provide training to ensure your employees get the most from our laser marking solutions. We equip a wide variety of industries and companies with laser marking solutions, and hundreds of organizations trust our state-of-the-art laser marking solutions. In addition, we can also provide you with customized laser marking machines according to your needs and will provide you with competitive prices.
AccTek
Contact information
Get Laser Solutions