Know About Laser Marking Machine.
Laser marking is the process of permanently marking a surface using a focused beam of light. It can be performed using different types of lasers, including fiber lasers, CO2 lasers, pulsed lasers, and continuous lasers.
How Does Laser Marking WorkTo create a lasting mark, laser marking systems generate focused beams of light that contain high levels of energy. When a laser beam hits a surface, its energy is transferred in the form of heat, creating black, white, and sometimes colored marks
Different Lasers to Mark Different Materials
Laser light energy is measured using wavelengths, or nanometers (nm). Specific wavelengths are used for different applications and can only be generated by certain types of lasers.
- Fiber lasers stimulate a rare-earth metal known as ytterbium to generate photons on the 1,064 nm wavelength. This wavelength is ideal to mark metals, as a good quantity of its energy is absorbed by the material.
- CO2 lasers stimulate CO2 gas to generate wavelengths between 9,000 nm and 11,000 nm, covering a wide range of organic materials that require different wavelengths. The most common wavelength for organic materials is 10,600 nm.
laser marking Applications
The three most common laser marking applications are:
- Laser engraving: creates deep and permanent marks that withstand abrasion
- Laser etching: creates high-contrast permanent marks at a high speed
- Laser annealing: generates marks under the surface without affecting the base metal or its protective coating
Laser marking can mark a variety of materials such as steel, aluminum, stainless steel, polymers, and rubber. It is often used to identify parts and products with 2D barcodes (data matrix codes or QR codes), alphanumerical serial numbers, VIN numbers, and logos.
The Main Differences Between Laser Marking, Etching and Engraving
Although these terms are often used interchangeably, there are differences between laser marking, laser etching, and laser engraving. Each type of process has its own applications and attributes that make it ideal for different jobs.
The Laser Marking Process
Laser marking is what happens when the beam interacts with the surface of a material, slightly altering its properties or appearance. Some of the features of the laser marking process include the following:
- It is achieved by moving a low-powered beam slowly across the material using a method called discoloration, which creates high-contrast marks without disrupting the material
- Laser heats the material, causing oxidation under the surface and turning the material black
- It applies low temperatures to metal to anneal the surface
- All of this is done while leaving the surface intact
Laser marking differs from laser engraving and laser etching in a number of ways, including the following:
- It is less common and not all places offer these services
- It is also referred to as laser coloration or laser dark marking, as well as charring for plastic materials and annealing for metals
- There are four common types of laser marking: annealing, carbon migration, foaming and coloration
- It’s popular in the medical device industry for stainless steel and titanium parts, but can be performed on other materials as well
- Laser marking is ideal for bar codes, UID codes, QR codes, logos and other identification needs
The Laser Engraving Process
Laser engraving is a process where the laser beam physically removes the surface of the material to expose a cavity that reveals an image at eye level.
- High heat is created during the laser engraving process, which essentially causes the material to vaporize
- It’s a quick process, as the material is vaporized with each pulse
- This creates a cavity in the surface that is noticeable to the eye and touch
- To form deeper marks with the laser engraving system, repeat with several passes
Although laser engraving is a subsection of laser marking, it still differs in many ways:
- There are three types of laser engraving: etching, deep laser engraving, and laser ablation (the difference between the three is what the surface is and how much you remove)
- This is the most common option for people who want something personalized or customized
- Laser engraving is not ideal for marking safety critical parts
- The maximum engraving depth is 0.020″ in metals but can go as deep as 0.125″ in materials such as graphite
- This is the fastest way to mark with a laser
- It’s great for parts expected to experience high wear
- It’s typically used to laser engrave serial numbers and logos, among other things
- You can engrave on almost any kind of metal, plastic, wood, leather, and glass surface
Another important comparison to make is how laser engraving compares to traditional engraving practices include:
- It can be done on a variety of materials
- It is more legible than traditional engraving for small objects, such as jewelry and watches
- It provides you with more font and style options
- There is a smaller chance of product damage or deformation over time
- Laser engraving machines are faster than traditional methods
The Laser Etching Process
Laser etching, which is a subset of laser engraving, occurs when the heat from the beam causes the surface of the material to melt.
- The laser beam uses high heat to melt the surface of the material
- The melted material expands and causes a raised mark
- Unlike laser engraving, the depth in laser etching is typically no more than 0.001”