Laser technology is the core of manufacturing processes like welding, cutting, and marking, thanks to its precision and accuracy. Among these processes, laser marking—particularly laser engraving—has become essential for product identification and traceability.
Successful laser engraving relies on a thorough understanding of the process and the use of high-quality equipment or the services of a reputable provider. This guide will introduce you to the laser engraving system, covering everything you need to know before integrating it into your project.
What Is Laser Engraving?
Laser engraving is a precision marking technique that uses a focused laser beam to vaporize the surface of a workpiece, creating a permanent design. A laser engraver, which is a type of laser marking machine, generates the laser beam and leaves a lasting mark on the material.
As a core process in laser marking, laser engraving stands alongside techniques like etching, annealing, and ablation. These methods share similarities in precision, durability, and versatility across different materials, but laser engraving excels in producing deeper, more durable, and highly contrasted marks.
Laser engraving creates marks that are typically deeper than those from other laser marking methods. The depth varies depending on the material and the laser engraver’s settings. The strong contrast between the marked and unmarked areas makes the engraving highly visible, though it might not be as pronounced as in laser etching.
Industries use laser engraving widely for product traceability, identification, and decoration. It effectively marks logos, barcodes, serial numbers, and QR codes on various parts and products.
Brief History of Laser Engraving
Its history cannot begin without talking about manual engraving. Before the advent of laser engraved parts, manual engraving was the only way to mark a product. Manually engraving a part involves using a sharp object (engraving tool) to inscribe the marking.
As far back as 500,000 years ago, stone was the most common engraving tool. However, recently, styluses made using metal parts have become common. Manual engraving even evolved over the years due to technological advancement leading to industrialization seen in dot peening and roll marking; however, the reliance on laser technology premised on Albert Einstein’s idea of LASER in 1916, and its optimization in the 1950s led to an industrial wide acceptance of laser marking over the former.
Theodore Maiman created the first optical laser, and Gordon Gould made the original laser light. Lasers later became an important part of drilling when Western Electrics made the first laser machine in 1965. However, its real use in engraving would not be until the advent of CO2 lasers in 1967. Advancements in technology later led to engraving machines like the UV and MOPA laser.
Is Laser Engraving the Same as Laser Cutting?
No, they are different. The engraving process uses a laser beam to remove material from the surface of an object, vaporizing or melting it to create a permanent mark. Hence, its application in product personalization and customization.
In contrast, laser cutting involves using a laser beam to cut entirely through a material. The laser cut the workpiece by melting, burning, or vaporizing it to produce clean, precise edges. It is a sheet metal fabrication technique commonly employed to cut materials like plastic, wood, fabric, and metal parts.
How Does Laser Engraving Work?
With an idea in mind and the steps highlighted below, you have all it takes to laser engrave a part:
Designing
Designing is the first step, and it involves creating a digital representation of the desired pattern, text, or image using graphic design software like Adobe Illustrators, Inkscape, and Onshape.
Afterward, the design is converted into a format compatible with the engraving machine. There are two common formats: Vector and Raster-based, each suitable for different design size, type, and complexity. Vector-based designs are especially popular because they allow the laser to follow precise paths, enhancing accuracy.
Material Preparation
Choose a material compatible with the laser engraver that complements your design. Generally, laser engravers can work on stone, glass, plastics, and metals. However, the types of engraving machines are suitable for a secluded list of materials.
For example, UV laser engravers (cold lasers) do not produce high heat, which limits them to plastics and thermosensitive materials. In contrast, CO2 laser markers are compatible with organic materials.
Laser Configuration
Configuring the laser involves adjusting the engraving parameters based on the material, desired marking depth, and quality requirements. This step is crucial as it directly impacts the final quality of the engraved part.
Key parameters to configure before engraving a part include laser power, speed, and frequency. Here is a short explanation for each parameter:
- Laser Power: This controls the beam intensity. Higher laser power creates deeper engravings, while lower power suits delicate work or thermosensitive parts.
- Speed: This determines how fast the laser head moves across the material. Slower speeds allow for deeper and more detailed engravings, while faster speeds are suitable for lighter markings.
- Frequency: This refers to the number of laser pulses per second. Higher frequencies are used for softer materials, whereas lower frequencies are better for harder materials.
- Adjust the laser focal point for correct alignment with the workpiece surface for sharp and precise engraving.
Engraving Process
The engraving laser machine uses the design instruction from the CAD model to direct the laser beam, which vaporizes the workpiece surface layer and creates the engraved pattern.
The precision of the engraved mark depends on the machine’s settings, while the ease of engraving depends on the machine’s type and sophistication. Sophisticated laser machines have advanced features like automation to ensure consistent and quality results.
There are two types of laser engravers: benchtop and portable. Benchtop engravers are stationary and are suitable for tasks requiring stability and accuracy. In contrast, portable ones are flexible and useful for on-site work and handling large or irregularly shaped parts.
Inspection
The final product is inspected once the engraving process ends to ensure it meets the desired specifications. Inspection includes checking the design accuracy, marking depth and clarity, and the overall quality of the finish. Any discrepancies are addressed by adjusting the laser settings and re-engraving if necessary.
5 Types of Laser Engraving Machines
In industrial engraving, the right laser machine can make all the difference. There are five main types, each with unique characteristics suited to different materials. These machines are:
Fiber Lasers
Fiber lasers, with power levels ranging from 20 to 50 watts, are celebrated for their versatility and strength. Their advanced filtration of monochromatic light beams allows them to work effectively across a wide range of materials, making them a top choice for precision marking.
These lasers are known for producing high-quality beams, offering exceptional durability and flexibility, particularly on complex surfaces. However, they are less suited for tasks involving thick or highly reflective surfaces.
CO2 Lasers
CO2 lasers, with a wavelength of 10,600nm, are equipped with sealed-tube systems and galvo-steered beams, making them ideal for engraving a wide range of organic materials such as wood, glass, ceramics, and plastics.
These lasers can also be used on metals, but require a special marking agent that bonds to the surface, creating a permanent, high-contrast mark.
While CO2 lasers are versatile, they do come with some drawbacks. Their high initial cost, combined with significant maintenance and operational expenses, makes them a considerable investment. Additionally, CO2 lasers consume a lot of energy and typically require longer processing times.
UV Lasers
UV lasers operate at a 355nm wavelength, utilizing ultraviolet rays that generate minimal heat. This low-heat characteristic makes them ideal for engraving materials with low thermal thresholds, such as those commonly found in the electronics industry, including circuit boards and microchips.
While UV lasers are highly efficient for precise, heat-sensitive applications, their lower power level limits their ability to engrave tougher materials like metals. The reduced heat output, while beneficial for delicate materials, also means that UV lasers are less suited for more demanding engraving tasks.
YAG Lasers
YAG lasers are compact, lightweight, and popular machines for marking thin metal sheets. They are suitable for marking materials such as aluminum and steel. Unlike other engraving machines, they produce low-power laser beams. Therefore, there is no material distortion during and after marking.
MOPA Laser Machines
MOPA laser marking machines are like fiber lasers based on their design and outlook. However, they have different internal technologies, which is evident in how the Master Oscillator Power Amplifier gives the machines high power efficiency.
The machine produces a highly coherent beam that is amplified without losing its properties. The frequency amplifies to 2700KHZ compared to the fiber laser’s 500KHZ. MOPA lasers are very versatile and are suitable for:
- Multiple color markings on stainless steel.
- High-contrast black marking on anodized aluminum.
- High contrast marking on plastics.
Materials Used for the Laser Engraving Process
The laser technique is compatible with many materials. Below are a few ones you can consider for your project.
Plastics
Plastics, in the engraving process, offer versatility, durability, and ease of modification and can be engraved with detailed designs, logos, and text. Hence, they are applicable in signage, electronics, personalized items, and automotive parts.
Acrylic (PMMA), polycarbonate (PC), and ABS are common plastics used in the laser technique.
- Acrylic is clear and durable, providing high-contrast engravings.
- Polycarbonate’s strength and impact-resistant improve its industrial use.
- ABS is tough and is applicable in 3D printing aid manufacturing.
Plastics absorb laser energy well, enabling precise material removal and marking. They are compatible with UV lasers, effective for delicate and detailed work, and CO2 lasers, effective for general engraving tasks.
Metals
Metals used in the process offer durability, and popular choices are stainless steel, aluminum, and brass.
- Stainless steel offers corrosion resistance and strength, which makes it suitable for industrial applications.
- Aluminum is lightweight and versatile.
- Brass provides an aesthetic appeal with its gold-like finish.
Fiber lasers are preferred for metal engraving due to their high power density and shorter wavelength (1064 nm), which efficiently mark metals. CO2 lasers can also be used for metal part engraving, but they require a marking spray or paste to absorb the laser energy and facilitate marking.
Woods
Wood is a versatile and natural material that engraves beautifully, offering a warm, traditional aesthetic. Different wood types react uniquely to laser engraving, resulting in a variety of textures and tones. Commonly engraved woods include hardwood, softwood, and plywood.
- Hardwood: Known for its durability and ability to capture rich details, making it ideal for intricate designs.
- Softwood: Easier to engrave, though it may lack the precision of hardwood, offering a softer, more subtle finish.
- Plywood: Provides a balanced option, combining ease of engraving with consistent results across various projects.
- The CO2 laser engraver is the most compatible tool for wood, delivering clean, detailed engravings on a wide range of wood surfaces.
Coated Metals
Engraving coated metals requires a delicate balance of precision and control to maintain the integrity of the protective or decorative layer, preventing exposure of the underlying material. Commonly engraved coated metals include anodized aluminum and painted metals.
For these applications, Fiber Lasers and MOPA (Master Oscillator Power Amplifier) Fiber Lasers are the preferred tools. These lasers allow for adjustable pulse durations, providing precise control over engraving depth and contrast. This precision ensures the coating remains intact while achieving the desired engraving results.
Composites
Composites such as carbon fiber and fiberglass are made from materials with different properties. The CO2 laser is best for these materials because it effectively engraves surfaces containing organic and synthetic components.
Advantages of Laser Engraving
The marking technique provides high precision, efficiency, and durability. It excels in creating detailed markings without altering material properties, making it a versatile and effective choice for various industrial applications. A few benefits of the laser marking process include:
Precision and Accuracy
It uses focused laser beams to achieve detailed markings, making it ideal for creating intricate designs and small text with high accuracy. This precision surpasses traditional methods like manual engraving or dot peening, particularly in industries that require detailed and consistent results, such as electronics.
Speed and Efficiency
Compared to many traditional marking methods like dot peening, scribing, and inkjet marking, engraving can be faster and more efficient. The process efficiency and speed can improve when using machines with advanced features such as automation and parameter adjustments, making it a preferred choice for high-volume marking.
High-Quality Finish
The laser’s precision ensures a clean, sharp finish without burrs or rough spots. This level of detail and consistency is important in products with high aesthetic value.
Non-Contact Marking
The laser beam does not physically contact the material, avoiding contamination or distortion of the workpiece’s properties. This is advantageous over methods like dot peening or inkjet marking, which can affect material integrity.
Flexibility in Design
The engraving technique is flexible as it supports the creation of complex and custom designs on various materials.
Disadvantages of Laser Engraving
The engraving process also has a few limitations that need to be considered before making a choice. They include:
Need for Expertise
Operating a laser engraver demands a thorough understanding of its settings, laser parameters, and potential troubleshooting. This requirement for technical knowledge can be challenging for small businesses or individuals without access to trained personnel.
High Initial Cost
Purchasing a laser engraver can be expensive, especially for advanced models. This high upfront investment may be a barrier for small businesses or hobbyists. Outsourcing to specialized engraving services can help mitigate these initial costs.
Operational Costs
It involves continuous costs, including routine maintenance, replacement parts, and energy consumption. Keeping the machine in optimal condition requires regular upkeep, which can be costly and impact overall affordability.
Limited to 2D
It is limited to creating surface-level designs and cannot produce three-dimensional patterns. This restriction can limit projects needing significant depth or intricate 3D details, requiring alternative methods for such applications.
Applications of Laser Engraving
Laser engraving is a versatile process widely used across various industries for product personalization, traceability, and non-colored identification. Some of the most common applications include:
Application | Description |
Engraved Plates and Tags | Precision and long-lasting markings make engraving ideal for creating vehicle identification plates and tags, such as nameplates, serial number tags, and equipment labels. |
Custom Engraved Gifts | The process’s precision and adaptability make it perfect for personalizing non-colored gifts, including jewelry, photo frames, and keepsakes. |
Signage and Displays | Detailed and attractive outcomes make laser marking a preferred technique for creating signage and displays, like business signs, directional signs, and display panels. |
Tools and Instruments | Durability and accuracy of laser engraved markings make them excellent for tools and instruments with identification numbers, calibration marks, and other essential information. |
Electronic Devices | In the electronics industry, laser marking ensures precise and clear labeling of components, circuit boards, and other devices with serial numbers, logos, and regulatory marks. |
What Are the Differences Between Laser Marking, Laser Etching, and Laser Engraving?
Difference Between Laser Marking and Engraving
Laser marking includes techniques that use laser technology to alter the surface properties of a workpiece, such as laser oxidation, annealing, carbon migration, etching, and engraving. Hence, laser engraving is a laser marking process.
A major difference between the two is material removal. The engraving process removes high material removal, leading to deeper engravings than other laser marking techniques. Consequently, the engraving process is also slower.
Another difference between the two is the characteristics of the marks. Unlike laser marking techniques, engraved marks have low contrast, no color option, and are long-lasting and durable.
Difference Between Laser Etching and Engraving
Laser etching melts the surface of a part to create a raised mark, while engraving vaporizes part of the workpiece surface to create an engraved mark.
A primary difference between the two laser marking techniques is the marking depth. Laser-etched marks are shallow with a depth of up to 0.001 inch. In contrast, engraved marks are deeper, up to 1.0 to 1.5 millimeters. The depth of the marking also leads to engraved marks being more long-lasting, while laser-etched ones have higher contrast due to their raised nature.
Another difference is the extent of material removal from the part. Laser etching has lower material removal compared to engraving. As a result, laser etching has a quick turnaround.
Difference Between Laser Marking and Laser Etching
Laser etching is a laser marking technique, like laser oxidation, annealing, carbon migration, and engraving. Like many laser marking techniques, except engraving, laser etching removes less material. Consequently, it is suitable for surface-level marking.
Similarly, the marking depth is comparable to other laser techniques except engraving, as it produces marks up to 0.001 inches deep. The speed of any laser marking technique depends on the marking depth. Hence, shallower laser-etched marks have quicker turnaround times.
Lastly, laser-etched marks have a high contrast due to the raised marks, providing clear visibility. This is similar to the laser annealing and oxidation techniques.
Comparing Laser Marking Techniques
Aspect | Laser Oxidation | Laser Annealing | Laser Carbon Migration | Laser Etching | Laser Engraving |
Material Removal | None | None | Minimal | Minimal to moderate | Significant |
Marking Depth | Shallow | Shallow | Shallow to moderate | Shallow (up to 0.001 inches) | Deep |
Speed | Fast | Fast | Moderate | Fast | Slow |
Color | Various colors (e.g., blues, browns) | Darker shades (e.g., blue, gray) | Generally black | Limited to material color | Monochrome |
Visibility | High contrast | High contrast with color changes | High contrast | High contrast | High visibility due to depth |
Durability | Suitable for surface applications | Suitable for surface applications | Durable | Good for surface applications | Long-lasting |
Typical Materials | Metals, ceramics | Metals, ceramics | Plastics, some metals | Metals, plastics, glass | Metals, wood, acrylic, plastics |
Conclusion
Understanding laser engraving technology and making informed decisions—whether by selecting the right equipment or outsourcing to a professional service—is essential for achieving optimal results. This article has provided you with a comprehensive overview of the engraving process, highlighting its key features and offering practical guidance to kickstart your project. By choosing the appropriate technology or partnering with RapidDirect, you can ensure precise, efficient, and high-quality engravings every time.
Start Your Laser Engraving Now
The best way to achieve a quality engraved part at a competitive cost is by outsourcing to a laser marking service provider. There are several benefits to opting for one. It includes offsetting the initial investment and ongoing expenses associated with purchasing and maintaining laser equipment for the service provider. These providers also offer flexibility for handling varying order sizes.
When selecting a service provider, consider factors such as the materials they handle, their facility and equipment, their experience, and their reputation. A service provider with a strong track record of consistent results and efficient customer support will better meet your needs.
RapidDirect offers comprehensive laser marking services with advanced facilities and a skilled team. Our experts are well-versed in material compatibility and engraving processes, providing valuable insights to ensure successful outcomes.
We also prioritize efficient operations and responsive customer support for a smooth experience. If you need reliable laser engraving, contact us.
FAQs
The process can vary in difficulty depending on the material, design complexity, and the engraver’s experience. Beginners may face challenges understanding machine settings, material compatibility, and safety procedures. With proper training and practice, these challenges can be managed effectively.
The longevity of a laser engraved part depends on the material and environmental conditions. Metal engravings, particularly on corrosion-resistant materials like stainless steel, can last indefinitely. However, engravings on plastic or wood may degrade over time, especially if exposed to harsh conditions.
Yes, fiber lasers are suitable for engraving metals and some plastics. They are known for their precision and are commonly used in aerospace, automotive, and electronics due to their effectiveness.
Fiber and CO2 lasers differ in wavelength and material compatibility. Fiber lasers operate at around 1064 nanometers, making them effective for metals. CO2 lasers operate at around 10.6 micrometers and are better suited for non-metal materials such as wood, acrylic, glass, and fabric. Fiber lasers are more efficient, require less maintenance, and have a longer lifespan than CO2 lasers.
Fiber lasers are ideal for engraving metal due to their wavelength of approximately 1064 nanometers, which is well absorbed by metal surfaces. They offer high-speed processing and low maintenance, making them a cost-effective choice for metal engraving.
The maximum depth achievable depends on the material, engraver, and exposure time. Fiber lasers can achieve depths of up to 1.0 to 1.5 millimeters in metals. CO2 lasers can achieve similar depths in non-metals like wood or acrylic.
Yes, they can work on curved surfaces, though they may require additional equipment or adjustments. Rotary attachments can hold and rotate cylindrical objects for even engraving, and advanced machines with 3D capabilities can adjust the focal length and laser path to handle curved or uneven surfaces.