Aluminum is one of the most prevalent materials in the manufacturing industry. Its fabrication is of utmost value. However, this material is solid, and cutting can be tedious. Fabricating it with old-school cutting methods would affect precision. Therefore, manufacturers prefer laser cutting aluminum to enhance precision.
However, many people consider this laser-cutting method unsuitable for aluminum. The sole reasons are the heat conductivity and reflectivity characteristics of this material. Are laser cutting methods efficient in cutting aluminum? There is a lot of confusion regarding this question. This article will bust all those misconceptions. So, let’s begin!
Overview of Laser Cutting of Aluminum
Laser cutting is an advanced technology that uses a very focused laser beam. The laser head directs the beam on the aluminum material. This laser beam has high energy, so it metals and vaporizes the material. In this way, the cutting and shaping of aluminum is done.
Conventional cutting methods were inefficient, compromising speed and precision. However, these laser-cutting methods are more advanced. They use a dedicated laser beam to melt and vaporize the material. Interestingly, these machines also come with a CNC system, improving their precision.
Aluminum is corrosion-resistant and a strong and less costly material. Manufacturers consider it ideal for making different parts. But their cutting is not as simple as one may think. They have high reflectivity, which is a big drawback. But these high-powered, concentrated, and focused laser beams are good enough to cut this material.
Modern laser-cutting machines come with a CNC system. The computerized system controls the movement of the head. The operator makes a design of the required shape. This design is changed in coded instructions and then fed to the computer. This computer uses this coded instruction and controls the movement of the head.
As a result, the laser beam remains very focused. So, it only cuts specific parts of the material and does not affect the whole aluminum material. Moreover, this laser cutting of aluminum is high-speed and reliable. This aluminum machining using CNC laser machines gives 100% precise output.
How to Laser Cut Aluminum?
Earlier, I mentioned this laser cutter technology’s essential nooks and crannies. But how does laser cutting work? What steps exactly are involved? These questions are the least understood as this topic is very complex. But fret not! I’ll explain everything about these cutters and their workings in simple steps.
1- Preparing the Design
All the CNC machines’ operations begin with creating the design. These CNC-based laser-cutting machines are no exception. So, first of all, you’ll have to design the shape you want from aluminum. Different software can be used to create specific designs.
However, operators use CAD software at this step. Why? Because it is easy to use and helps make very accurate designs. Remember, there is no hard and fast rule about what software you should use. It is totally up to your expertise. Moreover, consider hiring a CAD expert model designer if you hesitate to design.
2- Create Programmed Instructions
The design made through CAD will be converted into coded instructions. Remember, the computerized system can only understand these instructions. CAM software comes in handy when converting the design into coded instructions. Once programmed instructions are ready, the operator will feed them to the computer.
The CNC laser machines come with a dedicated computerized screen. This is where the operator controls all things related to these machines. Instructions will also be provided on this screen. The CNC system will control the movement of the laser head according to the instructions given.
3- Mount Material on the Worktable
Every CNC laser cutting machine comes with a worktable. This is where the material is clamped. In our case, we will use aluminum on this worktable. Clamping this material is essential. Why? Because it will help keep the aluminum steady while working. If it is unstable, it will move during the laser’s operation.
4- Setting the Machine Parameters
As I said earlier, laser-cutting machines have dedicated screens. The operator will have to put the specific parameters on this screen. Let me explain this with an example. The aluminum sheets have different thicknesses. The thin sheet would be easy to cut and vice versa. When dealing with thin sheets, operators will have to keep the intensity of lasers low.
Conversely, thicker sheets would require more intense and high-powered laser beams. The feed rate and cutting head are also adjusted properly. The feed rate is how fast the laser head moves on the material. Adjusting the cutting head ensures the proper angle at which the head emits a laser beam.
5- Cutting & Finishing Material
Once all the parameters are set, the operator switches on the machine. The computerized system reads the instructions. As a result, it moves the head of the laser machine accordingly. Remember, the head of the laser machine dictates the direction of the laser beam. Due to the CNC system, the movement of this head is accurate as per instructions.
So, the lasers will go on the material right at the point where users want. As a result, these beams will cut the aluminum accurately. Remember, aluminum has high reflectivity as well as high heat dissipation. However, the CNC system in laser machines ensures that the reflectivity of aluminum does not impact the precision.
Are you thinking about the HAZ (Heat Affected Zone)? You might not like it, but the laser cutting of aluminum creates HAZ. As you know, the laser beam consists of strong heat. The aluminum dissipates heat when a laser strikes it. So, the heat won’t be focused on specific areas and will spread to more areas.
As a result, you’ll see more areas affected by high dissipation. This will reduce the mechanical strength of this material. Due to HAZ, the manufacturers put the cut part through an additional finishing process. Why? This process smooths the edges and surface of the aluminum material. However, the finishing process adds extra cost, which could be a drawback.
Quick Highlight: You’ll get 100% precise cutting with a laser. Want precision? If yes, you’ll have to compromise with high HAZ. Using a laser machine is a kind of trade-off. You get excellent cutting precision, but their overall cost is relatively higher.
Types of Laser Beam Used in Cutting Aluminum
While explaining the aluminum cutting process, I skipped this information deliberately. Why? Because I wanted to explain this selection of laser beams in more detail. Remember, two types of laser beams are commonly used in aluminum fabrications. Those are as follows:
- CO₂ Lasers
- Fiber Lasers
However, fiber lasers are very prominent in the aluminum cutting process. Let me explain the logic behind their usage. As you know, aluminum has high reflectivity. So, it reflects more of the laser beams that strike its surface, right? However, these fiber lasers have very short wavelengths.
The aluminum material quickly absorbs most of these lasers due to their short wavelength. So, a very minimal reflection of the beam. Conversely, the CO₂ Lasers have a long wavelength of around 10.6 µm. The absorption of such a long wavelength laser beam is tedious. So, the aluminum will reflect most of these beams. So, fiber laser beams are used in aluminum cutting.
Challenges in Laser Cutting Aluminum
Cutting aluminum with a laser machine is possible. But, this cutting is not as smooth as one may think. Why? Because the aluminum material has some definite properties that go against laser cutting. In the section below, I’ll explain the properties of aluminum.
Remember, those properties make laser cutting hard but not impossible. The manufacturers cut and shape the aluminum with lasers at higher scales.
1- High Reflectivity
How many times have I said this in this article? You remember it by heart if you’ve been ready for a long time. Aluminum has high reflectivity. This means the laser or rays that strike the surface of aluminum bounce back. This reflection of the laser is terrible if it can affect the machine’s working as well.
Solution: Manufacturers use short-wavelength laser beams to cut aluminum. These beams are easy to absorb, and aluminum does not reflect most of these rays. This solves the issue of aluminum’s high reflectivity to some extent.
2- Strength & Thickness
Aluminum is not a weak material. Instead, it is super strong, and its sheets vary in thickness. Thin sheets of aluminum do not pose any issues during laser cutting. However, some aluminum sheets are very thick, and cutting such sheets can be tricky.
However, manufacturing uses high-power laser machines, which emit high-energy beams on the material. Such intense laser rays easily cut through thick material. Remember that you’ll have to adjust the laser power every time according to the thickness. The thin aluminum sheet will require a laser beam with less energy, and vice versa.
3- Heat Dissipation
This is one of the biggest challenges manufacturers face during laser cutting aluminum. Have you ever heard of ‘Heat Affected Zone’? These areas other than the target location become weak due to the impact of the laser. Let me explain how aluminum’s properties pose an issue. Aluminum has high thermal conductivity.
So, aluminum dissipates all the heat when a laser beam strikes the surface. Simply put, the heat of a laser does not remain focused at one specific place. As a result, more areas of aluminum material are impacted by heat. That’s why you tend to see those HAZ that weaken the material. Is there any solution to this higher thermal conductivity of aluminum?
Yes, modern CNC laser machines are very capable of handling this issue. Their computerized system controls the bombardment of laser beams. Moreover, these beams are powerful, concentrated, and focused. As a result, they only affect very targeted areas instead of more material. This machine reduces the HAZ, but that’s not a 100% HAZ-proof solution.
Quick Highlight: You might notice rough edges if you cut aluminum with these lasers. These are due to aluminum’s heat dissipation issues. Such parts undergo an additional finishing process. This process removes those rough surfaces and ensures smoothness. However, it adds some extra cost to aluminum cutting.
Advantages of CNC Laser Cutting Aluminum
Have you got the nitty-gritty of these laser-cutting processes? You might say that this laser cutting of aluminum is not very efficient. Aluminum does not support this laser cutting as it has some limitations. Do you think so? If that’s the case, you’re wrong. CNC laser machines are an excellent method of aluminum fabrication.
Here is why I support this cutting method:
- CNC laser machines offer 100% precision when cutting aluminum material.
- These machines can cut aluminum of any size and thickness. You can increase and decrease their laser’s power
- The laser cutting method is smooth and quick. You’ll get your desired part very quickly and with precision.
- The CNC-based laser machines don’t produce any waste during cutting. They cut the part that you exactly need.
So, the drawbacks are few, and the advantages are diverse. Manufacturers can easily tackle the potential limitations of aluminum materials. Therefore, the usage of laser cutting is increasing. Small to established businesses use these methods for fabricating aluminum.
Frequently Asked Questions
Can laser cut aluminum?
Yes, the lasers have high energy, so they can easily cut the aluminum materials. These lasers cut with precision and ensure quick turnaround.
How does laser cutting of aluminum work?
The laser machine emits a high-powered laser beam on the surface of aluminum. These beams melt and vaporize the material where they strike. Laser cutting of aluminum offers exact outputs, reducing material waste.
Is laser cutting aluminum expensive?
Yes, laser cutting aluminum is costly as compared to traditional methods. You’ll have to buy a dedicated laser-cutting machine, which is expensive. However, these machines are valuable to money in the long run. You’ll be able to cut aluminum quickly. It will enhance your productivity and efficiency.
Conclusion
Let me debunk popular confusion: lasers can cut aluminum of any thickness. Many people believe that cutting aluminum through lasers is not possible. That’s wrong—different laser-cutting machines of various power capacities are available. Moreover, some CNC-based laser cutting machines that give 100% precision are also available. This guide covers all the minute details of these machines.