All About Laser Cutting
In the last few decades, laser cutting has experienced more than a surge in popularity — it has become an indispensable part of world commerce. From fabrication to medicine and beyond, laser cutting is an industry seemingly without limits. Its products can be found everywhere. Lasers cut the silicon in microchips, perform corrective eye surgeries and craft the futuristic gear hurtling into space aboard rocket ships.
Still, there is a lot about laser cutting that most people still don’t know. How does it work and what are the mechanics behind it? What are all of its applications? What is the laser cutting process and how do you use it for your own project or business?
In this article, we will dive into everything you need to know about laser cutting. There is a lot to learn, starting with the technical aspects of how a laser cutter functions and then moving on to its many uses. Luckily, the technology is as accessible to the mind as it is to the consumer. Let’s get started.
What Is Laser Cutting?
Simply put, laser cutting is the process of using a laser to cut, score, engrave or otherwise alter physical materials. As futuristic as it sounds, laser cutting is a technology that has been with us for decades. Like many innovations, its scope was initially limited, but an incredible number of industries have since adopted it with great enthusiasm.
It can be easy to operate a laser cutter these days. Though the technology itself is the result of astounding feats of genius, the user interface has developed in a user-friendly way. It is common for hobbyists, school science classrooms and businesses to employ the use of laser cutters. They’re not just useful — they are a spectacular way to learn about optics and the properties of light.
Laser cutting starts, naturally, with a laser beam. The beam is focused until its intensity is sufficient for the job at hand, whether that’s cutting through metal, human tissue or cardboard. A computer program guides the laser itself and specifies the pattern the laser beam will cut. Once it begins, the laser will then follow the pre-programmed guide to complete its work.
Depending on the material and the desired result, the laser beam will both move around and vary its focal length. This way, it can reach different depths and cut different layers of material. With metals, this is useful for techniques like engraving. In other applications like medicine, however, its pinpoint accuracy allows it to cut medical devices.
Laser cutting is truly an amazing technology. It lies at the confluence of computers and the human touch. Its applications are already broad, but more will undoubtedly emerge as technology continues to improve.
Let’s look now at the mechanics of a laser cutter and how it does what it does.
How Does Laser Cutting Work? Here Are the Basic Mechanics
The word “laser” stands for “Light Amplification by Stimulated Emission of Radiation.” In a laser cutting device, it all starts with the laser resonator. This component creates the laser beam, in which light particles of the same wavelength travel out of the resonator in the exact same direction. This beam might be in the invisible infrared area of the spectrum, in the case of a CO2 laser, or of some other wavelength as required by the application. When it exits, it may be about .75” in diameter.
This beam of parallel light waves is then reflected off one or more mirrors into the focusing head. Once inside the focusing head, the beam is sent through a series of lenses. These, predictably, focus it. It then passes out through a nozzle and sears whatever it lands on. You’ve seen this effect before. In the same way that sunlight through a magnifying glass can start a fire, shining a laser beam through a focusing lens creates an incredibly powerful, singular point of light.
That means all the photons in the laser beam converge at a single point. How could this be? The more physics-oriented reader may cry, “Pauli Exclusion Principle!”, which roughly states that two particles cannot occupy the same space at the same time. However, since photons are not technically matter, they are exempt from the Pauli Exclusion Principle and can exist at the same point in space. That means all the energy in that .75” laser beam is now focused into one point in space.
You can imagine what happens next. The point on the material where this intense light strikes is instantly melted or vaporized.
What Happens to the Material During Laser Cutting?
We have an incredibly intense confluence of laser light striking a surface. But what happens next? How is the depth of cutting controlled and how do we account for different types of material?
As it turns out, we left out one component of the laser system above. It’s the addition of compressed gas to the laser beam’s path. As the beam converges past the focusing lens, it is joined by a stream of fast-moving gas. This is typically oxygen or nitrogen. The gas flows downward and shoots out of the nozzle, which the laser also passes through the tip of, and impacts the zone where the laser is cutting.
Oxygen might be used for a material like soft steel, which the laser will cause to ignite. The oxygen will then make the burning steel incinerate and disappear from the site. In other metals such as aluminum or stainless steel, where the laser beam simply causes the metal to melt, nitrogen is used. As the metal melts, a jet of gas blows down with it and removes the molten metal from the kerf.
The kerf is the slit made by the laser. Its width is adjusted by focusing the laser at different heights relative to the surface.
Uses and Applications of Laser Cutters
As we have said, laser cutting is an exciting industry full of continuously new developments. Here are some of the most common applications of laser cutting today.
Not only does laser cutting work on a large number of metals, but it is also a versatile tool between industries. Laser cutting can make smooth, tight cuts that are cleaner than those made by machining. Like machining, it too can be programmed and guided by a computer, meaning a laser cutter can automatically create large numbers of metal parts for cars, computers and more.
Metals undergo many different operations in laser cutting. Often, strange shapes such as automobile frames or hydro-formed parts need laser cutting, as do many parts in the aerospace industry. The results are often better than with plasma cutting.
- Reflective Metals
Why mention reflective metals when we’ve already mentioned metals? Because reflective metals bounce backlight that shines upon them, which this raises concerns when directing a high-powered laser beam at them. If the metal were to reflect the laser, it could destroy itself.
The answer to this problem comes in the form of fiber laser cutting. With this technique, fiber optic cables transmit the laser beam to the metal. Any light reflected does no damage to the fiber optic cable. Metals such as aluminum, silver, copper, and gold are all reflective and are vitally important in the production of automobiles and semiconductors.
- Medical Sciences
Laser cutting also plays a huge role in the medical industry, where extreme precision and tight dimensional tolerances are essential. Because of the medical industry’s demand for high volume, this technology aligns with their needs in that it can replicate designs with both accuracy and a quick turnaround.
Medical devices of many types have their origin in laser cutting, from cardiovascular and orthopedic devices to components for surgical implants. With laser cutting, these devices can be made with the required rapidity without sacrificing accuracy.
- Engraving and Marking
A slightly less graphic application of laser cutters can be found in the world of engraving and marking. This is also where the laser cutter frequently enters the mainstream market. Many metal signs, insignias and other metal works are produced through engraving and marking. When jewelers need an engraving, they frequently turn to laser cutters.
However, the process is not just limited to metals. Wood also responds well to laser cutting. Wooden signs, pictures, and even decorative topographical reliefs are all products of this technology.
Our world very much runs on silicon. It makes up our microchips, our solid-state semiconductors and a host of other things related to computers and electronics. It is also a large player in the important field of solar energy, which has a growing potential to power our world. Laser cutting is one of the primary ways silicon is cut for use, so it is difficult to exaggerate exactly how important the technology is.
Part of the reason technology consistently shrinks in size and increases in capacity is thanks to laser cutting of silicon. Laser cutters have grown increasingly precise — as a result, they can cut smaller and smaller pieces of silicon.
The Benefits of Laser Cutting
Laser cutting is an incredible technology that serves a huge chunk of the world’s industries. Its benefits continue to grow in number as the technology improves and as more applications find it useful. Here is a list of reasons why it is so popular at the moment:
- It is versatile with respect to materials. Laser cutting is not limited to any one material or even subset of materials. Laser cutting works with a huge number of metals, ceramics, woods, plastics, rubbers, silicon and more, and is finding new applications all the time.
- Kerf widths are narrow for fast and accurate cutting. The kerf width in laser cutting can be incredibly thin, which means less material is wasted, the cuts are more precise and efficiency is higher. The turnaround times in laser cutting are relatively quick, too. Additionally, shapes, patterns, and operations can be repeated accurately. The robotics involved in laser cutting are highly sophisticated. If a process requires automation or repetition, you can be sure laser cutting will produce high-quality output.
- The technology is reliable and setup time is short. Laser cutters have become extremely reliable thanks to improvements in technology, meaning you don’t have to worry about your systems failing. This prevents backups and delays. Programs make designing your product quick and easy.
- If you need to make a change mid-production, it is easy to do. If you find out at some point during production that you need more, less or a slightly different variation of a product, laser cutters can pivot quickly and adapt to the change in demand.
- Processing is efficient. If you want to do multiple jobs at once, overlap projects or do some other variation on the norm, laser cutters can accommodate the request.
- There is no need to clean most materials after laser cutting. Unlike many other processes, laser cutting does not leave a mess. You won’t have to deburr or sand-down your products because the laser cutting process leaves it smooth. In many cases, you can pull the product out of the cutter and send it off to be shipped.
- The technology is always advancing and becoming greener. Laser cutters are energy-intensive, but they are becoming vastly more efficient. Additionally, CO2-based lasers are increasingly being replaced by fiber-optic lasers.
- There is huge potential to combine with 3D printers. 3D printing is gaining steam in the same way laser cutting has. It’s likely that the two technologies will combine to produce spectacular possibilities in the near future.
Come to Laserfab to Learn More About the Possibilities
At Laserfab, we are a one-stop shop for your laser cutting needs. Along with our outstanding customer service, we offer a trusted partnership, top-quality products, highly skilled professionalism and consistent value. When you contact us, we start by giving you a free quote.
We keep materials in stock — including steel, stainless steel, and aluminum — in a wide variety of thicknesses. We can offer accelerated lead times, too. Laserfab’s service becomes an extension of your production team, providing parts that are ready to seamlessly integrate into your WIP.
Laserfab becomes a true partner in your supply chain and works with you to solve your pain points in getting your products to market. We nourish this partnership with engineering support at the beginning of the project and expedite your parts through production as well as outside services such as powder-coating. Our mission isn’t fulfilled until you receive your parts on time and they meet with your approval.
Contact Laserfab today to get started and let us help you take your business and production quality to the next level.