Modern manufacturing often requires extreme precision on exceptionally tough materials. Cutting processes that gave great results half a century ago are no longer acceptable. Innovative cutting technologies have been developed to meet the requirements of modern industrial cutting.
One of the best cutting methods in this day and age is laser cutting. It has gained much traction and is being applied across many sectors. Professionals new to the technology wonder what is laser cutting and how it works.
This article will discuss laser cutting technology, its pros and cons, applications, and additional helpful information.
What is Laser Cutting?
Laser cutting uses a high-energy laser beam to cut through any material. Laser stands for Light Amplification by Stimulated Emission of Radiation. It is one of the most popular types of industrial cutting processes. Lately, laser cutters have also become prevalent in small workshops, hobbyists, businesses, and schools. Laser cutting works on cutting every material regardless of its physical properties.
Continuous and Pulsed Laser Beam
Laser beams work in two ways- continuous and pulses. Continuous laser cutting uses a light beam for a long period without intermittent breaks. The pulsed mode uses high-energy laser beams for a short time. The compression of pulses allows for high energy density of the beam.
Who Invented Laser Cutting?
The earliest use of the laser cutting process dates back to the 1960s. Theodore Maiman invented laser technology in 1960. The application of this technology occurred in 1965 for making holes in diamond. The cutting process was quickly adopted for other applications. By the 1970s, laser cutting had become a commercial process for titanium cutting in the aerospace industry.
Development of Laser Cutting Technology
Laser cutting technology saw many quick developments since its invention in 1960. Elias Snitzer developed the concept of fiber lasers in 1963. However, it took two decades to refine this technology fully for commercial applications. Working for Bell Labs, Kumar Patel invented the CO2 laser in 1964. It was a very powerful laser with a continuous operating mode. It gained huge popularity quickly. The developments in the next few decades integrated laser cutting with another emerging technology- Computer Numerical Control (CNC).
Main Components of Laser Cutting Machines
Laser cutters work on the concepts of optics like reflection and amplification. The whole working of a laser cutting machine can be broken into two individual systems- the optical system and the mechanical system.
The optical system generates a high-powered laser beam for the cutting process. The mechanical system moves the laser beam around to create the desired shape. Parts of a basic laser cutting system are:
- Power Supply: The power source helps generate the light beam.
- Laser Resonator: A laser resonator is an assembly of mirrors. It reflects the light beam in the gain medium for amplification.
- Cutting Head: Cutting head focuses the laser beam on the desired point of contact.
- Mechanical System: The mechanical system involves motors and rails. They move the cutting head around the workpiece.
- Motion Control System: The motion control system directs the motors and arms on where to move the laser.
These are only the basic components of a laser cutting system. Modern commercial laser cutters have a lot more parts like cooling stations, dust extractors, and slag discharge systems.
Working Process of CNC Laser Cutting Machines
Laser machining technology offers a lot of different features for different industries. Regardless of features, the basic working process of most of these machines is the same. Here are the steps to the working of a CNC laser machine:
1. Loading the G-Code
The machine’s work starts when the operator loads the G-code on the system. The G-code instructs the laser cutting machines on the movement directions.
2. Generation of Laser Beam
Once the machine operation begins, the laser resonator generates the light beam. The process of laser generation can be different for various type of lasers. The color of laser can also be different. For instance, in CO2 lasers, laser generator emits an infrared light. This laser beam is entirely visible to human eyes.
3. Directing the Laser
A direction system diverts the laser beam to the focussing system. A series of mirrors can change direction. A specialized beam bender can also bend the generated laser to the focussing area.
4. Laser Focusing
A focussing system reduces the width of the laser beam and increases its power. This is done with a laser focusing head and a focusing lens. The focusing system also ensures that the focused laser beam is completely round with no stray light. The laser beam emits the machine through a nozzle.
5. Material Cutting
The focused laser beam is directed to the workpiece material. The point of contact is exposed to the laser beam long enough to melt the material. The duration of exposure varies on material thickness and type.
6. Cutting Head Movement
The mechanical system moves the laser head in the required shapes, as the G-code directs. The speed of movement varies based on the particular job.
What are the Different Types of Laser Cutting Processes?
Many different variations of the laser cutting process are popular for particular applications. These different types of laser cutting processes are:
CO2 Laser Cutting
In CO2 laser cuttings, the laser amplification occurs through a CO2 gas discharge. CO2 lasers are one of the earliest and most popular types of lasers. The gas discharge isn’t entirely Co2. It contains CO2, Nitrogen, Hydrogen, Xenon, and Helium.
C02 laser cutting comes with two options: using Oxygen or Nitrogen gas. Oxygen gas is preferred for laser cutting thicker materials. Nitrogen gas is preferred for laser-cutting thin sheets. Using oxygen C02 laser cutting creates an oxide layer on the cut surface. Pre-treatment processes such as blasting are done on the workpiece to avoid this.
Fiber Laser Cutting
Fiber lasers use optical fiber for light amplification instead of conventional gas discharge. Light emitted through laser diodes passes through the optical fiber. The resultant light beam is sufficiently strong to melt away stainless steel up to 1 cm in thickness.
A strong airflow system often accompanies the light beam. The airflow pushes away the molten material for a clean cut. The fiber optics of these lasers utilize several elements like Ytterbium, Neodymium, Erbium, and Dysprosium.
Nd:YAG Laser Cutting
Nd:YAG stands for Neodymium-doped Yttrium Aluminum Garnet (Nd:Y3Al5O12). Nd:YAG crystals are used in lasers for amplified beam instead of gas discharge or fiber. These lasers are capable of both continuous and pulsed laser beam.
Excimer Laser cutting
Excimer stands for Excited Dimer. Excimer laser cutting uses an ultraviolet laser beam. Excimer laser cutting is used in small-scale precision cutting processes. Some common examples are eye surgery, microelectronics, and semiconductor cutting.
Direct Diode Laser Cutting
Direct Diode Laser (DDL) uses a laser beam directly from the diodes. There are no amplification mediums like gas discharge or fiber. The diodes directly produce a strong enough laser beam for the cutting process. Direct diode laser cutting has a very high efficiency.
Different Techniques in Laser Cutting
Laser cutting is not all about dividing a material in two parts. There are many different techniques in the laser cutting process. These techniques greatly expand what a laser machine is capable of.
Here are all the different ways in which you can use a laser cutting machine:
Vaporization Cutting is also known as Sublimating. Usually, on heating, solid materials reach the melting point and then the boiling point. However, in vaporization cutting, the laser beam raises the temperature of the material at a very fast speed. The material directly reaches the boiling point and begins to vaporize. There is no melting caused and no time for heat conduction. This results in a very precise and narrow cut.
This cutting process only applies to the thin sheet metal of ferrous materials. It does not apply to materials that don’t have a boiling point, like wood. Additionally, it requires a very high-powered laser beam to work.
Fusion cutting is also known as Melt and blow cutting. Melt and blow cutting is the basic form of laser cutting. The laser beam melts the workpiece material. A blower then removes the melted material, thereby separating the workpiece. The melt and blow cutting method can cut thicker materials with ease.
It is important to use an inert gas in the fusion cutting technique. Non-inert gas will react with the workpiece due to the material’s high temperature. Inert gas flow ensures no inadvertent chemical reaction occurs.
Laser Flame Cutting
Laser flame cutting is also known as reactive cutting and oxidation melting cutting. Oxygen gas aids in the cutting process in addition to the laser beam. Oxygen gas is blown to the workpiece along with the laser beam. The laser ignites the oxygen, which turns into a high-temperature blow torch. The material is weakened with the oxygen flame and the laser heat, resulting in faster cutting.
Laser flame cutting is considerably faster than other laser cutting techniques. However, the cut quality and accuracy deteriorate. Additionally, the kerf width increases in this method. It is possible to replace oxygen with any other reactive gas.
Fracture Controlled Cutting
Fracture-controlled cutting is also known as thermal stress cracking. It is applied when cutting brittle materials. When uncontrolled force or temperature is applied, brittle materials tend to break into pieces. Fracture-controlled cutting focuses a very narrow laser beam on a small workpiece surface. It creates a thermal gradient that cracks the workpiece in that location. The laser then moves in a very fast and controlled manner to spread the crack along the cut.
Fracture-controlled cutting is commonly applied when cutting glass and ceramics. The laser is not passing completely through the material thickness. Only a portion of the thickness is cut and the rest separates due to cracking.
Stealth dicing is an advanced laser-cutting technology used for slicing semiconductor wafers. It works in two phases- the laser irradiation phase and the expansion phase. The laser does not melt the workpiece because that would create unwanted molten material. Instead, the irradiation phase uses a laser wavelength that passes through the workpiece completely.
However, this wavelength creates internal deformations and cracks in the workpiece. The expansion phase then creates expansive stress on the workpiece. This stress separates the workpiece into many pieces at the areas of internal defects. The end result is a clean-cut wafer with no dross.
Vector scoring is a laser-cutting technique for engraving the workpiece. The laser does not pierce through the entire thickness of the material. Instead, the laser will follow the travel direction specified by the vector.
The thickness of the engraving can be easily adjusted by defocusing the laser beam. The depth of the engraving can also be adjusted. Vector engraving can create simple, straight lines to complex designs.
Laser Cutting Machine Configurations
There are three different configurations for laser cutting machines:
Moving Material Configuration
In moving material configuration, the laser head is completely stationary. The workpiece material is moved relative to the laser cutting head. The benefit is that there is a single location where the removed material is accumulated. This makes material extraction easier. However, the cutting speed of this process is slower because moving a large workpiece is more difficult than moving the small cutting head.
Another main advantage of moving material configuration is that the laser’s travel distance remains constant. Therefore, fewer optics are required.
The hybrid configuration has a partial movement of the material and partial movement of the cutting head. Conventionally, the material moves along the X-axis, and the laser moves along the Y-axis since the latter is shorter.
The distance that the laser beam travels is not constant. When the cutting head moves in Y-axis, the distance between the resonator and the cutting head will keep on changing. Therefore, some compensation is required to keep the power of the laser constant. This is done by increasing optics in comparison to moving material configuration. However, the working process of these lasers is faster.
Flying Optics Configuration
Flying optics configuration has a movable cutting head but a stationary work table. The cutting head can move in both the X and Y axis. Flying optics configuration provides a faster cutting speed among all three options.
However, the laser distance constantly changes as the cutting head moves. This requires a complex optics setup that can account for the variable distance.
What Materials Can Lasers Cut?
Laser cutters can cut most materials with very few exceptions. Some of the materials that can be cut with a laser cutter are:
Laser cutters are becoming the preferred cutting tools in most metalworking shops. Metal cutting industry uses lasers for making incisions on many different forms of metal. Common variants of metals cut with lasers are sheet metal, rods, pipes, and tubes.
Cutting materials with a laser is different from cutting wood or ceramics. The main challenges are the thermal conduction of metals and their reflectiveness. These challenges are overcome by reducing the workpiece’s exposure area and increasing the laser beams’ intensity.
Some common metals and alloys that are cut with laser cutting are:
- Steels (like carbon steel, mild steel, stainless steel, etc.)
Plastics are a little tricky to cut with a laser. Unlike sheet metal, some plastics release toxic fumes upon being heated at extreme temperatures. Therefore, knowing what plastics you can cut with laser cutting is important.
Some of the plastics that are quite suitable for laser cutting are:
Laser cutting is one of the best ways to cut wood. Lasers can work on all types of wood without any exceptions. Laser engraving on wood is almost as common as laser cutting procedures. The only thing to consider is the wood thickness. For woods thicker than 20 mm, waterjets can provide better results.
Some of the common woods that laser cuts are:
- All types of hardwoods
Laser cutting works great for fabrics and textiles. Conventional cutting methods often fray the fabric edges. However, laser cutting produces no such unwanted effect. The high heat of the laser creates a clean cut and a sealing effect on the fabric’s fibers.
Some of the common fabrics that are cut with a laser are:
Laser-cut paper is often used for cardboard boxes, packaging products, dioramas, and decorative applications like wedding invitations and bunting. Additionally, the consistency produced by laser-cutting paper is second to none.
Laser cutters make smooth cuts on foam without any rough edges. However, ensuring that the foam you cut does not release any toxic fumes on heating is important. Some safer foams to cut with a laser are polyurethane, polyethylene, and polyester. Some foams, like Expanded Polystyrene foam, are flammable and don’t release damaging fumes. These require extra caution while cutting with a laser.
Glass is a very brittle material and uneven force or unbalanced heat can easily crack it. Therefore, laser cutters use fracture-controlled cutting for glass. Etching on glass with a laser is also very common. It is particularly used for decorative items like trophies and panels.
The brittle nature of ceramics is similar to that of glass. Therefore, ceramic cutting and etching are usually done with fracture-controlled cutting. Ceramic tiles are the most common example of laser cutting. Laser engraving is common in pottery items.
What Materials Are Unsuitable For a Laser?
Laser cutters can cut through any material. However, there are some materials that you should not cut with a laser cutter. The materials unsafe for laser cutting are:
- Fiberglass: Fiberglass contains a material known as epoxy resin. Epoxy resin emits toxic fumes on cutting with a laser.
- Polypropylene Foam: Polypropylene foam tends to catch fire very easily. It melts after catching fire, and the melting drops keep on burning. It does not self-extinguish. When the melted drops cool off, they turn into extremely hard drops.
- ABS: ABS can catch fire very easily. Additionally, it also melts, which results in unwanted and hard-to-remove deposits. Heated ABS also releases toxic cyanide gas that can harm the human workforce.
- PVC and Vinyl: PVC and vinyl release chlorine gas when heated with a laser. Chlorine gas can destroy the laser cutter by corroding the metal parts and ruining the optics.
- Thick Polycarbonate Sheets: Polycarbonate sheets thicker than 1 mm can catch fire when cutting with a laser. Additionally, these sheets can also discolor and have a poor cut edge.
- HDPE: HDPE is flammable when it comes in contact with laser heat. It catches fire, melts, and creates unwanted deposits.
Pros and Cons of Laser Cutters
Laser cutters come with a lot of benefits and a few limitations. Let us go through each one by one:
What are the Advantages of Laser Cutting?
- Accuracy: Laser cutters have the highest precision among any cutting methods. The high precision comes from the light being narrowed down to an extremely thin diameter. The accuracy is even higher than processes like water jet cutting.
- Speed: Laser cutting thin materials is extremely fast. The speed can easily be over 3 meters per minute. Therefore, laser cutters are common in mass-production assembly lines.
- Versatility: Laser cutting works on a lot of different applications and for many different uses. This makes it a very versatile cutting method.
- Customization: It is possible to create personalized and customized shape by simply changing the CNC program.
- Automation: Modern CNC laser cutters work with CNC systems. CNC can automatically control the movement of the cutting head.
- Dust-free Cutting: Using a laser does not create any material dust in the workpiece. For instance, there is no sawdust when cutting wood with fiber lasers.
- Less Waste: A laser cutter is very precise and removes very little material from the workpiece. This leads to minimum material waste. It is extremely useful when cutting precious metals where wastage can lead to losses.
Disadvantages of Laser Cutter
- Budget: Laser cutters are industrial equipment. It can be tricky to fulfill their initial investment and maintenance costs if you are on a tight budget.
- Safety: Safety is not a big limitation with modern lasers as they come with safeguard measures. However, the operator still requires safety training.
- Unsafe Materials: Certain materials are unsafe for cutting with a laser. It is important to know these materials beforehand to avoid machine damage and human injury.
- Thickness: Laser cutting works well for thin materials like sheet metal. However, it doesn’t work for thick materials like metal blocks.
What are the Applications of Laser Cutting?
Laser cutting is used in almost every sector nowadays. Some of the common applications of this process are:
A laser cutter is common in the automotive sector for sheet metal cutting. It makes components like exhaust systems, frames, suspensions, and other body parts.
Aerospace applications have precision as the top priority. Laser cutter turns out to be the perfect solution for the job. Lasers in aerospace are used for making aircraft frame parts, turbine blades, and other smaller components.
Fiber lasers are a common sight in the assembly line of manufacturing plants. This includes metalworking workshops, textile mills, plastic parts, and more.
A laser cutter can conveniently make consistent parts for electronic devices like TVs, smartphones, laptops, tablets, and more.
Advertising materials like cutouts, signage, and brand logos use a laser cutter for smooth edges and aesthetic appeal.
Lasers can make decorative products for the architecture industries. Common examples are cladding and art installations.
Laser power is used in the healthcare industry for making medical devices. Additionally, surgical equipment also uses laser systems.
Laser Cutting Design Software
Laser-cutting software ease the job for the machine operator while improving cut quality and precision. Laser design software are simpler than CNC programming. An important thing about laser design software is that it creates a vector file for the laser machine. Vector files are not like pixel images. Therefore, vector files do not lose any quality on resizing.
Design Tips for Laser Cutting
Accurl has many tips you can follow to get outstanding results on your laser-cutting project. Some of the design tips that can help you are:
- Remember to choose the right format for the vector file. Commonly accepted formats are dxf, eps, step, and ai. Image formats like jpg and jpeg are not acceptable.
- Never use text boxes in the design file. Laser cutters don’t understand the text. Instead, convert the text to shape-based designs. For instance, create ‘W’ with four inclined straight lines.
- Choose the right material for your project. Find out if the material you chose is right for laser cutting.
- The simplest design is the best design. Complex designs will give problems while cutting and are susceptible to breaking.
Laser Cutting Tolerance
Tolerance in cutting refers to the deviation of the actual after-cutting part from the intended design. Lower tolerance means higher accuracy. When comparing two processes for accuracy, you should evaluate their tolerance values. The lower tolerance process will have high precision.
Laser cutting provides tolerance less than +/- 0.01″. This value is among the lowest in any industrial cutting technology. This is why laser cutting is one of the most precise processes out there.
Laser Cutting Maximum Thickness
A common query regarding laser systems is the maximum thickness they can cut. The exact value of maximum thickness varies based on the particular material. For instance, laser light can cut mild steel up to 2.5 cm (1 inch) thickness. For other materials, the maximum thickness lies in the range of around 2 cm. Laser power also determines the maximum thickness. High power laser can cut thicker materials than low power consumption laser.
Dangers of Laser Cutting
Laser processing systems can have certain dangers associated with them. These machines are designed to cut through the hardest materials by melting them. Therefore, the power of these machines is extreme. Understanding the dangers of these machines is vital before operating them.
Modern laser systems come with multiple safeguard measures to eliminate such concerns. However, to ensure a safe operation, getting a high-quality laser system is important. Accurl is the best choice in this regard.
Environmental Impact of Laser Cutting
The environmental impact of a laser cutter depends on how you use it. Laser cutting has a certain carbon footprint since it is an industrial technology. However, the energy consumption of these machines is quite lower than comparative cutting tools.
Additionally, laser cutters also reduce material wastage. Good quality CNC machining lasers last for ages without needing replacements. All these factors favor making laser cutting an environmentally friendly technology.
Is Laser Cutting Cost Effective?
Yes, laser cutting is a very cost-effective cutting process. Fiber lasers start at around $4000 and go up to $300,000. Other types of lasers also have a wide price bracket. Therefore, you can get a machine in your price range. The average operating costs of these machines is very cheap at around $12 per hour. When you consider these machines’ output and capabilities, they are the best option in terms of cost efficiency.
How Long Do Laser Cutters Last?
Fiber laser cutters can easily last for around 100,000 hours. This equates to over 45 years of usage. On the other hand, a carbon dioxide laser lasts for only 30,000 hours. This equates to around 15 years of usage. There are some consumables in every laser that will require replacement after regular intervals. For example, the tubes can last for around 500 hours and need changing afterward.
Where to Buy a Laser Cutter?
Accurl is a leading manufacturer of fiber laser cutting machines. Accurl laser cutters are the preferred equipment for the leading manufacturers in many sectors. These machines are a global standard of quality. Being a global brand, there is never a difficulty with spare parts or technical assistance.
If you are confused about which laser cutter to buy, you can decide based on the following factors:
- Laser technology: The different types of lasers differ remarkably in the results they provide. Most professionals recommend using fiber lasers as they balance quality, cost, and speed.
- Budget: Lasers have a wide price range. Set a budget before you decide on a machine.
- Quality: Good quality machines come with safeguards and a rugged build. Opt for a brand like Accurl instead of a local machine manufacturer.
- Bed Size: The bed size will define the maximum workpiece area you can accommodate. Choose it based on your industry application.
- Floor Space: Ensure that the machine you get will easily fit in your workshop.
What are the Alternatives to Laser Cutting Technology?
Here are some of the alternative cutting techniques that industries use and their performance in comparison to laser cutters:
Water Jet Cutting
Water jet cutting stands its own against laser cutters. Waterjet provides the benefit of no molten material since it is a cold-cutting process. Laser, however, provides benefits such as a better edge and higher precision. The lack of water requirement is another point in favor of laser cutters.
Plasma cutting also works by melting the material at the cut area. However, plasma cutting only works for electrically conductive materials like metals and alloys. This is a huge disadvantage of the process. Laser cutters can work on any material. They also provide engraving properties.
EDM cutting removes material by electrical discharges. Like plasma cutting, EDM is also limited to conductive metals. However, laser works on all materials and provides better results. Laser is also capable of engraving, but EDM is not.
CNC machines like mills and lathes rely on physical cutting tools. These tools wear out fast due to friction with the material. However, a laser requires no physical tools. Additionally, laser cutters provide better precision than CNC machines.
Punching creates cutouts through the physical force of the die. Punching can be a cheap metalworking process. However, the quality and precision of punching is quite poor. Laser cutters provide much better results.
3D printing is used for the additive manufacturing of plastic materials. They cannot replicate the results of laser machines. 3D printed products have significant defects that are often visible. The results of 3D printers are quite inferior to a laser machine. Additionally, 3D printers have a limited material range.
Laser cutting techniques are the go-to method for any application that requires precision and quality incisions. Laser marking processes take the capabilities of the technology a step further.
Lasers can cut the hardest materials and easily engrave workpieces without cutting them completely. If you are looking for industrial cutting equipment for your workshop, laser cutters can be the perfect fit.
Get in touch with Accurl to know which laser cutter will be the right fit for you.