The world of laser cutting is not standing still. With the emergence of the fiber laser as an inexpensive laser cutting option, many sheet metal workers are wondering if they should switch to this new technology.
Currently, there are 3 types of laser cutting machines on the market for industrial use. The CO2 laser, the Nd:YAG laser and the fiber laser, with the latter being considered the successor to dee Nd:YAG lasering. The difference between these three options is mainly in the laser source they use. Which one is the best choice for you? Is the new fiber laser technology something to consider?
The fiber laser has its advantages over CO2 laser cutting technology. A high cutting speed and lower energy consumption make this an interesting option to look at. But in practice it turns out that it mainly depends on the application whether you can actually achieve a better result with this.
There are also many other aspects to consider. Cost, maintenance, consumption, etc..
In this article we will therefore explain the difference between a fiber and CO2 laser and what applications they are best suited for. We hope to help you find the right machine for your needs.
Table of Contents
The CO2 and fiber technologies work in different ways that are fundamentally different. The technology is obviously very complex, but without getting too technical we can give you the differences in operation.
A CO2 laser can actually be compared to a fluorescent tube. Electricity is sent through a tube with a carbon dioxide, nitrogen, hydrogen and helium gas mixture. This stimulates the nitrogen molecules and increases their energy. In other words, they start to vibrate. This then also stimulates the carbon dioxide molecules in the mixtures.
To produce light, these molecules must release their energy. This happens when they come into contact with the helium atoms.
This tube is surrounded by mirrors and these cause the light produced to increase in intensity as it reflects back and forth through the tube. At the end of the tube is a mirror that only partially reflects. When the intensity of the light is high enough to be transmitted, you have produced a laser beam.
In addition to nitrogen, it is also possible to use a gas mixture based on acid tuff. With oxygen, larger thicknesses can be cut, but an oxide skin is created on the cutting surface and it can break down. With nitrogen, you get a clean cutting surface, but it is less smooth and burr formation can occur.
The most powerful CO2 laser machines in the world have powers beyond 1000W. The ones used as cutting applications usually have power between 25 and 100W.
Fiber laser machines produce light with laser diodes and use a fiber optic cable to produce a laser. Fiberglass (also called optic fiber) provides the name for this type of laser.
A laser diode consists of 2 semi conductors that are charged differently. The first is positively charged, it needs an extra electron. The second is negatively charged, meaning it has an electron in surplus. When the positive and negative charges meet, this free electron is released as a photon and sent into a fiber optic cable.
The fiber optic cable consists of two components, namely a fiber core and the jacket. Light is transported through the fiber core, but since it is light, it naturally wants to go in all directions. However, the casing is reflective and will keep the light within the fiber core.
Then this light is further amplified in a laser cavity and a laser window is formed.
The basic harware of fiber laser machine is smaller than CO2 lasers. The light is produced by electronic components and moved through a fiber optic cable. So there are fewer large parts on it than in a machine where we have to work with gas mixtures.
However, this does not mean that the machine will take up less space in your building. The size of the machine is of course also determined by the size of the materials you want to process. A fiber laser system has no range limitation since the length of the fiber optic cable does not affect the system that much. So there is no limit to the size of the cutting table.
With the CO2 lasers the light beam is directed by mirrors, therefore there is a limitation in the distance that a mirror must be placed. The size of the cutting table is limited.
For what application should the laser be used?
There are many ways in which laser machines can be used and many products that are manufactured with them. From marking and cutting materials to optical and medical applications. In industry, however, it is mainly about processing materials.
The types of materials that can be cut with a laser are very diverse. And not every laser type is suitable for every material. This is because each laser has a wavelength at which it operates. With a fiber laser, this is about 1 micrometer. With CO2 lasers, the wavelength is 10x greater. This ensures that the absorption coefficient of both devices is very different.
And this absorption coefficient is indeed what it is all about when we talk about suitability for certain materials. You can actually look at a laser as a concentrated beam of light. As with ordinary visible light, some materials are more boxy than others. If the material absorbs little light at a given wavelength, there will also be little interaction between beam and material.
A CO2 laser beam that you send through glass will be almost completely absorbed by the glass. Whereas a fiber laser beam will pass through it unimpeded. Therefore, a CO2 laser can engrave glass, but a fiber laser cannot. Therefore, for organic materials such as leather, fabric, acrylic, wood, stone etc… the CO2 laser machine is always the best option. The fiber laser is not suitable for this.
Metals, on the other hand, are highly reflective. Most wavelengths have little absoption. However, the wavelength of a fiber laser is in the infrared region. Therefore, the absorption does exceed that of a CO2 laser.
In both cases, in order to cut metals such as stainless steel, aluminum, brass or steel, a very high power output is required. Here again, the fiber laser has the advantage. For thin plate, a fiber laser is not only faster, but the electrical efficiency is many times higher.
In recent years, thicker sheet metal work was still mainly done with the CO2 laser. That still gave the best results. They have faster piercing times and a smoother cutting surface for thicker materials. But here, too, the fiber laser is on the rise. The technology has improved tremendously in a short time. Meanwhile, you can cut up to 80mm thick with powers of 20 kW. While the same application can consume up to 120 kW with a CO2 laser.
CO2 lasers, on the other hand, are ideal for plastics. If you want to mark PVC pipes, electronic components or building materials, they are very suitable. For permanent marking such as serial numbers or barcodes, fiber lasers are more suitable. The focal diameter of fiber lasers is a lot smaller. This allows for razor-sharp laser engraving.
There is also a growing market for removing paint, rust and other contaminants for which fiber lasers are increasingly used. And also when cutting foil, a fiber laser is recommended. Because of the faster pulse times, the film does not have time to deform, which would happen with higher power lasers.
So it’s a question of the right tool for the right job. Are you curious what suits your application best? Bodor is happy to give you advice!
Of course, in addition to the technology and the many features of both types, there is something else that matters in your choice. Namely, what is all this going to mean for my bottom line.
For the purchase of a fiber laser system, much depends on the application and the power of the machine. The purchase price starts at 40 000 euros, but can go up to 1 000 000 euros.
The cost of CO2 lasers is usually lower than that of fiber lasers. It is usually between 35 000 and 80 000 euros. Again, the power (usually between 20 and 150W) is a major influence.
However, the purchase price is not the only cost of these systems. The operating costs are very different.
Fiber lasers are significantly more economical than CO2 lasers when it comes to power consumption. CO2 lasers require much higher power. Making a detailed comparison is difficult. Much depends on the size of the system and the application you are going to use it for.
What we can tell you is that a fiber laser will use a lot less energy to achieve the same results. For example, let’s say we are going to cut a material thickness of up to 5 mm at the same speed with a 1.5 KW fiber laser cutting machine. To do this same work at the same speed we need a 3KW CO2 laser cutting machine.
So the operating costs of a fiber laser are significantly lower.
The fiber laser is a faster device. But it’s important not to get caught out by that! The cutting speed is only part of the story. There are factors such as braking and accelerating the machine that affect the production speed. There are also differences in quality.
First of all, you have to ask yourself how complex the pieces you want to machine are. If you are cutting a lot of straight lines and simple contours, the fiber laser is significantly faster. However, the more complex the piece becomes the smaller the differences become. Then the production speed is determined not only by the cutting speed, but also by the cutting acceleration. For very complex pieces, a CO2 laser may well win the race.
For thicker materials to be cut, quality is also increasingly becoming a factor. Indeed, with a fiber laser, the cutting surface becomes rougher as the thickness increases. Also in making the starting hole, CO2 lasers are significantly faster with larger material thicknesses.
It is therefore important to look at your application and inform yourself well specifically for your operation.
When it comes to maintenance costs, we have a hard time getting around it. A fiber laser needs hardly any maintenance. CO2 laser cutting machines require a gas mixture to function. This leads to a certain contamination of the system, so it needs to be cleaned regularly.
There are also no mirrors and lenses that need to be not only cleaned but also aligned. A fiber laser does not require calibration.
This also gives a fiber laser a much longer life. If you choose a CO2 machine, you will have to take this cost seriously! Fiber lasers have a serious point for this.
The difference between the CO2 and fiber laser, the conclusion
In simple terms, you can say the following:
If your application is suitable for a fiber laser this is your recommended option. Especially for simpler workpieces, the system is faster and the production is therefore higher. The maintenance costs are virtually eliminated, the operating costs are significantly lower and the life cycle is longer. This gives a fiber laser serious fincancial advantages over time.
If you make very complex pieces, if a lot of detail depends on it or if you do prototyping, then a CO2 laser is more interesting because of the low start-up costs.
Fiber lasers are still relatively new and will only get better in the coming years. So if a fiber laser does not yet meet your needs. Keep an eye on this market for the future!