What is laser cutting? A beginner's guide to the laser process
What exactly is laser cutting? Laser cutting is an advanced machining technique in which a focused laser beam is used to cut materials such as metal, plastic and wood with extreme precision. This technology has revolutionised metalworking in the Netherlands and ranks among the most important innovations in modern production processes. Laser cutting works by locally heating material to its melting or vaporisation point, after which a cutting gas blows away the molten material.
The development of laser technology has led to unprecedented precision in the manufacturing industry. With accuracies down to 0.05 millimetres, manufacturers can produce components that were previously impossible to make. This technology is a key part of the trends in the manufacturing industry and contributes to the competitiveness of Dutch companies on the global market.
The physical principle behind laser cutting
Laser cutting works on the principle of controlled heating and material removal by means of a focused beam of light. The laser generates a coherent light beam with high energy intensity that is focused onto an extremely small point on the workpiece. This intense concentration of energy heats the material locally to temperatures exceeding its melting or vaporisation point.
The process begins in the laser resonator, where an active medium such as CO2 gas, neodymium or fibres is excited by electrical energy. This excitation causes atoms to release energy in the form of photons, which are amplified and bundled into a coherent laser beam. The beam is guided through a system of mirrors and lenses to the cutting head, where it is focused to a diameter of just a few hundredths of a millimetre.
During the cutting process, the intense heat creates a melt pool in the material. A cutting gas, usually oxygen, nitrogen or argon, is blown under pressure through a nozzle to remove the molten material from the cut. This gas serves several functions: it prevents oxidation of the cutting edge, cools the area around the cut, and ensures clean removal of the molten material.
Different types of lasers for cutting processes
There are various types of lasers, each with specific properties suited to particular materials and applications. The choice of laser type largely determines the quality, speed and cost of the cutting process.
CO2 lasers are the most traditional and widely used type of laser in industry. These lasers use carbon dioxide as the active medium and produce infrared light with a wavelength of 10.6 micrometres. CO2 lasers are particularly effective for cutting thick metal plates and non-metallic materials such as wood, acrylic and textiles. They offer a good balance between cutting speed and edge finish.
Neodymium lasers, including Nd:YAG (neodymium-doped yttrium aluminium garnet) lasers, produce light with a shorter wavelength of around 1.064 micrometres. This property makes them particularly suitable for cutting reflective materials such as copper and aluminium, which can cause problems with CO2 lasers. Neodymium lasers can operate in both continuous and pulsed mode.
Fibre lasers represent the latest generation of laser technology and are rapidly gaining ground in industry. These lasers use an optical fibre as the active medium and produce light with a wavelength comparable to neodymium lasers. Fibre lasers offer superior energy efficiency, lower maintenance costs and excellent beam quality, resulting in very high cutting speeds and outstanding edge finish.
The cutting process step by step
The laser cutting process consists of several carefully coordinated steps that together deliver an accurate and efficient result. Each step is crucial to achieving the desired quality and precision.
Preparation begins with designing and programming the cutting path. CAD software is used to draw the desired part, after which CAM software optimises the cutting path for efficiency and quality. This involves determining factors such as cutting sequence, lead-in and lead-out points, and cutting parameters.
The workpiece is then positioned and clamped on the cutting machine. Modern laser cutting machines are often equipped with automatic material handling systems capable of loading and positioning large plates. The machine calibrates the laser focus to the material surface, which is essential for optimal cutting quality.
During the actual cutting process, the cutting head moves along the programmed path while the laser cuts through the material. The laser's speed and power are continuously adjusted to the type of material, its thickness and the desired quality. Advanced systems can make real-time adjustments based on sensor feedback.
After cutting, the part is removed from the machine and any post-processing can take place. This may include deburring, cleaning or further machining steps. Waste residues are separated for recycling, contributing to sustainable production.
Materials suitable for laser cutting
Laser cutting can be applied to a wide range of materials, each with specific properties and challenges. The choice of material influences not only the cutting parameters but also the quality of the final result.
Carbon steel is the most common material for laser cutting and delivers excellent results. The high absorption of laser energy by iron enables efficient cutting, while adding oxygen as the cutting gas accelerates the process through exothermic reactions. Thicknesses up to 25 millimetres can be routinely cut with high quality.
Stainless steel requires a different approach due to its lower thermal conductivity and higher melting point. Nitrogen is often used as the cutting gas to prevent oxidation and achieve a smooth cutting edge. Cutting speeds are lower than for carbon steel, but the quality can be excellent.
Aluminium poses a challenge for lasers because of its high reflectivity and thermal conductivity. Fibre lasers have largely overcome this challenge thanks to their shorter wavelength, which is better absorbed by aluminium. Special cutting gases and adjusted parameters are needed for optimal results.
| Material type | Maximum thickness (mm) | Cutting gas | Typical speed (m/min) | Notes |
|---|---|---|---|---|
| Carbon steel | 25 | Oxygen | 15-20 | Excellent edge finish |
| Stainless steel | 20 | Nitrogen | 8-12 | Oxidation-free cutting |
| Aluminium | 15 | Nitrogen/Argon | 10-15 | Requires fibre laser |
| Copper | 8 | Nitrogen | 5-8 | High reflectivity |
| Brass | 10 | Nitrogen | 6-10 | Zinc vaporisation possible |
Advantages of laser cutting over other techniques
Laser cutting offers considerable advantages over traditional cutting methods such as plasma, water jet or mechanical cutting. These advantages have led to broad acceptance of the technology in the manufacturing industry in the Netherlands.
The precision of laser cutting is unrivalled in the world of thermal cutting. With tolerances down to 0.05 millimetres, parts can be produced that fit directly without further machining. This accuracy is achieved thanks to the small heat-affected zone and the stable focus position of the laser.
The speed of laser cutting is particularly high, especially for thin materials. Modern fibre lasers can reach speeds of 20 metres per minute or more at plate thicknesses of 1-2 millimetres. This high speed, combined with the ability to cut complex shapes without tool changes, results in short lead times.
The versatility of laser cutting is a major advantage. A single machine can process different material types and thicknesses, cut complex geometries and even perform engraving and marking operations. This flexibility is especially valuable in modern make-to-order production, where small batches and quick changeovers are the norm.
The automation possibilities of laser cutting fit perfectly with the industrial automation trends. Modern systems can run unmanned 24/7, with automatic material handling, quality control and even maintenance. This automation improves not only efficiency but also the consistency of production.
Limitations and drawbacks of laser cutting
Despite its many advantages, laser cutting also has limitations that are important to understand for proper application of the technology. These limitations can affect suitability for specific applications.
Thickness limitations are a significant constraint of laser cutting. Although modern lasers can cut thicknesses up to 25-30 millimetres, cutting quality and speed decrease as thickness increases. For very thick materials, alternative methods such as plasma or water jet cutting can be more efficient.
Reflective materials such as copper and aluminium were long problematic for lasers, especially CO2 lasers. Although fibre lasers have largely solved this problem, these materials remain more challenging than carbon steel and require special precautions and adjusted parameters.
The investment and operating costs of laser cutting systems are considerable. Modern industrial lasers can cost hundreds of thousands of euros, and the maintenance costs for components such as optics and resonators can add up. These costs must be weighed against the benefits in productivity and quality.
Safety aspects require special attention with laser cutting. Laser light can cause serious eye and skin damage, and the fumes released during the cutting process can be hazardous. Adequate extraction systems, safety enclosures and training are essential.
Quality aspects and accuracy
The quality of laser cutting is determined by various factors that must be carefully controlled and optimised. These quality aspects are crucial to the success of the process and the acceptance of the end products.
Edge finish is one of the most visible quality aspects of laser cutting. A well-cut edge is smooth, straight and free of burrs. Quality is influenced by factors such as laser power, cutting speed, gas pressure and focus position. Modern systems can achieve edge finishes that are directly usable without post-processing.
The heat-affected zone (HAZ) is the area around the cut where the material has been structurally altered by the heat of the laser process. A smaller HAZ is desirable because it means the material properties have been less affected. Laser cutting produces one of the smallest HAZs of all thermal cutting processes.
Dimensional accuracy is essential for many applications. Modern laser cutting systems can achieve tolerances of ±0.05 millimetres across the entire plate, provided the machine is correctly calibrated and maintained. This accuracy is achieved through advanced CNC control and compensation for thermal effects.
Straightness of the cut edge is important for applications where parts must be welded or otherwise joined together. Laser cutting can produce very straight edges, with deviations of less than 0.1 millimetres across the material thickness under optimal parameters.
| Quality aspect | Measurement parameter | Typical value | Determining factors |
|---|---|---|---|
| Edge finish | Roughness Ra (μm) | 1-5 | Power, speed, focus |
| Accuracy | Tolerance (mm) | ±0.05 | Machine stability, calibration |
| Straightness | Deviation (mm) | <0.1 | Gas pressure, speed |
| HAZ width | Width (mm) | 0.1-0.3 | Power, speed |
| Burr formation | Height (mm) | <0.05 | Parameter optimisation |
Modern developments in laser technology
Laser technology is continually evolving, with new developments constantly pushing the boundaries of what is possible. These innovations are part of the broader digital transformation in the manufacturing industry.
Adaptive optics represents a revolutionary development in laser cutting. These systems can adjust the focus position and beam quality in real time based on sensor feedback. This results in consistent cutting quality across the entire plate, regardless of variations in flatness or material thickness.
Artificial intelligence and machine learning are increasingly being integrated into laser cutting systems. These technologies can optimise cutting parameters based on historical data, predict material variations and even detect problems before they occur. AI-driven systems can also automatically select the best nesting software for maximum material utilisation.
Hybrid machining centres combine laser cutting with other machining processes such as punching, bending and engraving on a single machine. This integration reduces setup times, improves accuracy and enables more complex parts to be made in a single clamping.
Ultrashort pulse lasers open up new possibilities for machining difficult materials and ultra-thin layers. These lasers can vaporise material without significant heat input, resulting in exceptionally clean cuts with no heat-affected zone.
Economic aspects of laser cutting
The economic viability of laser cutting depends on various factors that must be carefully analysed for each specific application. This analysis is crucial for companies considering an investment in laser technology.
The initial investment in a laser cutting system can be considerable, ranging from hundreds of thousands to millions of euros depending on the power, table size and level of automation. These costs must be weighed against the expected improvements in productivity, quality and labour savings.
Operating costs include electricity consumption, consumables such as cutting gases and optical components, and maintenance costs. Modern fibre lasers are significantly more energy-efficient than older CO2 lasers and have lower maintenance costs, which reduces the total cost of ownership.
The payback period for laser cutting systems can vary from a few years to less than a year, depending on the application and production volumes. Factors such as reduced machining time, elimination of tooling costs, improved material utilisation and lower labour costs all contribute to the return on investment.
Flexibility and responsiveness are important economic benefits of laser cutting. The ability to switch quickly between different parts without tool changes makes small batches economically viable and shortens the time-to-market for new products.
What are the main advantages of laser cutting?
The main advantages of laser cutting are its exceptional precision with tolerances down to 0.05 millimetres, high cutting speeds especially for thin materials, excellent edge finish that often requires no post-processing, great material flexibility, minimal heat-affected zone, and the ability to cut complex geometries without tool changes. These advantages make laser cutting ideal for high-quality production applications.
Which materials can be cut with a laser?
Laser cutting is suitable for most metals, including carbon steel, stainless steel, aluminium, copper, brass and titanium. Non-metals such as acrylic, wood, textiles, leather, cardboard and various plastics can also be cut. The choice of laser type largely determines which materials can be optimally processed, with fibre lasers excelling at metals and CO2 lasers being versatile across different material types.
What is the maximum thickness that can be cut?
The maximum cutting thickness depends on the material type and laser power. For carbon steel, thicknesses up to 25-30 millimetres can be cut with industrial lasers; for stainless steel this is around 20-25 millimetres; and for aluminium typically 15-20 millimetres. For thicker materials, cutting speed decreases and costs increase, meaning alternative cutting methods can become more economical.
How accurate is laser cutting?
Laser cutting is one of the most accurate cutting methods, with dimensional tolerances of ±0.05 millimetres or better under optimal conditions. Repeatability is excellent, and the edge finish can be so smooth that post-processing is not required. This accuracy is achieved thanks to the small focus diameter of the laser beam, advanced CNC control and minimal mechanical forces during the process.
What are the costs of laser cutting?
The costs of laser cutting vary greatly depending on material type, thickness, complexity and volumes. Factors that influence costs include cutting speed, energy consumption, consumables such as cutting gases, machine depreciation and labour costs. For standard carbon steel, this can range from a few euros per metre of cutting length for thin plates to tens of euros for thick materials. Quotes are usually based on cutting length, material use and processing time.
How does the cutting gas work in laser cutting?
Cutting gas serves several functions in laser cutting: it blows molten material out of the cut, prevents oxidation of the cutting edge, cools the cutting zone and can chemically support the cutting process. Oxygen is used for carbon steel because it causes exothermic reactions that accelerate cutting. Nitrogen is used for stainless steel and aluminium to achieve oxidation-free cuts. Argon is sometimes used for special applications.
What is the difference between CO2 and fibre lasers?
CO2 lasers produce infrared light with a wavelength of 10.6 micrometres and are excellent for thick steels and non-metals. Fibre lasers have a shorter wavelength of around 1 micrometre, are more energy-efficient, have lower maintenance costs and are superior for reflective materials such as aluminium and copper. Fibre lasers also offer higher cutting speeds for thin materials and better beam quality, but CO2 lasers remain more cost-effective for very thick materials.
What safety measures are needed for laser cutting?
Safety in laser cutting requires protection against laser radiation through complete enclosure of the machine, safety goggles during maintenance, adequate ventilation for fume extraction, operator training, emergency stop procedures and regular inspection of safety systems. Laser light can cause permanent eye damage, and the fumes released can be toxic depending on the material. Compliance with laser safety standards such as EN 60825 is mandatory.
Laser cutting remains one of the most promising technologies in the modern manufacturing industry, with continuous innovations creating new possibilities for precision, efficiency and quality. The technology plays a crucial role in the competitiveness of Dutch companies and contributes to innovative production processes. Also listen to the