Before understanding laser cut aluminum, we have a preliminary understanding of aluminum through the following introduction.
What are the characteristics of aluminum?
Aluminum is a rich metal, accounting for about 8% of the weight of the earth’s crust.
Like brass, copper, silver and gold, it is a non-ferrous metal.
Nonferrous metals refer to metals other than iron or steel. Many of them have the characteristics of light weight and good conductivity.
Aluminum is light, soft but durable, which makes it easy to cut or shape on a laser cutting machine.
Unlike iron or steel, aluminum has the function of rust and corrosion prevention.
Due to the high flexibility of aluminum, the waste is usually the least, and any remaining waste can be recycled.
Can laser cut aluminum plate?
CO2 lasers or fiber lasers can be used to cut thin non-ferrous metal sheets.
However, when cutting with carbon dioxide laser, it is necessary to coat the material surface to avoid the reflected light from damaging the laser device.
Fiber laser can be directly used for non-ferrous metal cutting.
Aluminum can be cut by various types of cutting machines, such as laser, plasma, waterjet or mechanical cutting machine.
Compared with traditional aluminum cutting machine, the main advantage of laser cutting machine lies in speed and quality, and its processed workpiece is smoother and defect free.
How thick the aluminum plate is cut by the laser cutting machine depends on the power of the laser.
Generally, the 6000W laser cutting machine can cut max 16mm thickness, and 4500W laser cutting machine can cut up to 12mm, but the processing cost is high because it is a highly reflective material.
Laser cutting is to use the focused high-power density laser beam to irradiate the workpiece, so that the irradiated material can quickly melt, vaporize, ablate or reach the ignition point, and blow away the molten material with the help of the high-speed air flow coaxial with the beam, so as to cut the workpiece.
3 types of laser cutting equipment that can cut aluminum plate
In recent years, the innovation of laser technology makes people evaluate the advantages of laser cutting aluminum. The laser cutting process can process consistent parts faster.
It is more efficient than traditional processing.
Laser cutting technology will greatly reduce processing time and production cost.
Laser cutting equipment that can cut aluminum plates on the market is divided into three categories, namely
- Carbon dioxide laser cutting machine
- Fiber laser cutting machine
- Lamp pumped laser cutting machine
CO2 laser cutting machine
The laser wavelength of carbon dioxide laser cutting machine is 10.64um, which is easier to be absorbed by nonmetals.
It can cut wood, acrylic, PP, plexiglass and other non-metallic materials with high quality.
However, when cutting high reflective materials such as aluminum, copper and silver, most of the energy is reflected and lost, resulting in a great reduction in the practicability of the machine.
Moreover, the photoelectric conversion rate of CO2 laser is only about 10%, and the cost of replacement and supply of liquid nitrogen, electricity consumption and supporting cooling system is huge.
It can only cut the aluminum plate to a thickness of 3mm, which discourages most aluminum plate cutting customers.
Fiber laser cutting machine
It is a new type of fiber laser developed in the world, which saves more space and gas consumption than carbon dioxide laser cutting machine.
The wavelength of 1.06um is also more suitable for cutting metal materials.
At present, the fiber lasers on the market are mainly IPG continuous light lasers, which are reliable in quality but expensive in price, but few laser manufacturers can compete with them, which makes the price of the whole fiber laser machine remain high.
At the same time, if one fiber in the laser is damaged, the whole laser must be replaced. This maintenance cost also makes the majority of customers hesitate.
Fortunately, due to fierce competition and technology upgrading, the price of fiber laser cutting machine has been falling again and again, which also allows more users to choose it.
YAG laser cutting machine
YAG laser cutting machine also has a wavelength of 1.06um, which is also suitable for metal cutting.
YAG laser technology is a mature laser technology widely recognized and used for a long time in the international community.
The beam quality and the characteristics of pulsed laser are suitable for the cutting process of metal materials, and the energy utilization rate is high.
At the same time, the low purchase and use cost has also attracted more and more customers.
What are the advantages of aluminum plate laser cutting machine?
1. The aluminum plate laser cutting machine has high precision, the laser cutting incision is narrow and smooth, and there is no fillet and common rough mouth of mechanical blanking; The heat affected zone, thermal stress and thermal deformation are small.
2. The laser cutting machine has fast cutting speed.
3. High efficiency. The laser cutting machine is non-contact processing, without the impact force during mechanical blanking, without the wear of tools and molds, without the tower edge during mechanical blanking. The workpieces are closely arranged, which can save 20% – 30% of the materials. The cutting is formed at one time without subsequent processing.
How do laser cutting machines cut aluminum plates?
Laser cutting is to focus the laser emitted from the laser into a laser beam with high power density through the optical path system.
The laser beam irradiates the surface of the workpiece to make the workpiece reach the melting point or boiling point. At the same time, the high-pressure gas coaxial with the beam blows away the molten or gasified metal.
With the movement of the relative position between the beam and the workpiece, the material will finally form a slit, so as to achieve the purpose of cutting.
Laser cutting process uses invisible beam instead of traditional mechanical knife.
It has the characteristics of high precision, fast cutting, not limited to cutting pattern, automatic typesetting, material saving, smooth incision and low processing cost.
- It will gradually improve or replace the traditional metal cutting process equipment.
- The mechanical part of the laser cutter head has no contact with the workpiece and will not scratch the workpiece surface during operation;
- The laser cutting speed is fast, the incision is smooth and flat, and there is generally no need for subsequent processing;
- Small cutting heat affected zone, small plate deformation and narrow cutting seam (0.1mm ~ 0.3mm);
- The notch has no mechanical stress and no shear burr;
- High machining precision, good repeatability and no damage to the material surface;
- NC programming, can process any plan, can cut the whole board with large format, no need to open the mold, economical and time-saving.
Process parameters of laser cut aluminum
|1800- 2200||2000-2300||2200- 2400||2400- 2800||2600- 3000||3000|
|Speed||2000- 4000||2000-3000||1000- 2000||800- 1000||300- 500||400|
|Air pressure KPA||10||15||18||20||20||22|
|Minimum power change||80- 100||90- 100||100||100||100||100|
|Hole cutting parameters||Power
Technical analysis of laser cutting aluminum materials
From the perspective of cost and investment, the widely used aluminum laser cutting equipment are fiber laser cutting machine and YAG laser cutting machine.
These two types of equipment have good performance in cutting aluminum or other materials, such as stainless steel and carbon steel.
Because the aluminum plate is a highly reflective material, neither optical fiber laser cutting machine nor YAG laser cutting machine can process thicker aluminum.
In addition, nitrogen is recommended when laser cutting aluminum plates.
Because of the special color of aluminum and in order to ensure the uniform color of cut products, nitrogen can well prevent oxidation and retain the characteristics of the material itself. Nitrogen is a better choice.
Cutting thickness: 2000W laser can cut 6-8mm, 4000W can cut 12mm, 6000W can cut 16mm.
The optical fiber laser cutting machine is more suitable for cutting aluminum plate, and its wavelength absorption effect of 1064nm is better.
From the experience of laser cutting aluminum materials for many years, the difference between the two is still large, which is divided into three levels.
- Cutting quality
- Cutting speed
- Production cost (the production cost here mainly refers to the life loss of equipment)
1. Cutting quality
Aluminum profile is a highly reflective material, so neither optical fiber laser cutting machine nor YAG laser cutting machine can cut thick aluminum.
In addition, aluminum materials are not resistant to high temperature and are prone to burrs in the process of cutting aluminum materials. Therefore, it is necessary to focus on controlling the process to obtain ideal cutting quality.
2. Cutting speed
The cutting speed also needs to be controlled.
Too fast cutting speed is easy to produce burrs. Too slow cutting speed will cause cracks in aluminum materials, which will affect the cutting quality, so process control is needed.
Generally speaking, for the laser cutting equipment with the same power, the cutting speed of the fiber laser cutting machine is higher than that of the YAG laser cutting machine.
3. Production cost
The processing cost of laser cutting machine is very low, which is far lower than other cutting processes.
As a comparison between fiber laser cutting machine and YAG laser cutting machine, the cost of fiber laser cutting is lower than that of YAG laser cutting machine, which requires frequent replacement of laser lamp accessories.
However, in the long run, aluminum material has serious damage to the laser of the fiber laser cutting machine, which greatly reduces the service life of the laser. From this point of view, the cost of YAG is lower than that of the fiber laser cutting machine.
In addition, it should be noted that aluminum has high reflectivity and low absorption of laser. Therefore, laser protective glasses need to be worn during processing to protect their own safety.
What gas is used for laser cutting aluminum?
Nitrogen or air can be used to cut 1.6mm aluminum.
The surface of aluminum plate cut with nitrogen is smoother, and there may be slight slag hanging on some sections of aluminum plate cut with air.
The auxiliary gases that can be used by laser cutting machine mainly include oxygen, nitrogen, air and argon.
1. Laser cutting will produce a lot of heat. When such high heat is concentrated together, the material at the cutting place will burn and oxidize, and it is easy to deform the workpiece. Therefore, we need to add some auxiliary gases, such as oxygen, air and nitrogen.
2. When processing stainless steel, we should choose nitrogen. Nitrogen can prevent the oxidation reaction of the incision, so that the processed incision will not be blackened. When selecting nitrogen, choose high purity.
3. If it is processing carbon steel plate, oxygen should be selected. Oxygen mainly plays the role of combustion supporting, which can speed up the processing speed of workpiece. Of course, the purity of oxygen should be as high as possible.
4. In some processing requiring less precision, we can also choose oxygen, because the use of oxygen has low cost and great auxiliary effect.
5. In addition to the above functions, these auxiliary gases have many common functions. These gases can blow away the slag generated during cutting, protect the lens, prevent the slag from sticking to the lens and prolong the service life of the lens. Air and nitrogen can also cool the cutting head.
Will there be burrs in laser cutting aluminum?
The products cut by laser will have some burrs.
How to solve it?
It depends on whether you use manual grinding or machine grinding.
Manual grinding needs to be rough, and the efficiency is very low.
Of course, it is also cost – effective to invest in machines, that is, labor is saved and the polished products should be high-grade
13 details of safe operation of aluminum laser cutting machine
1. Observe the safety operation regulations of general cutting machine. Start the laser in strict accordance with the laser starting procedure.
2. Operators must be trained, familiar with equipment structure and performance, and master relevant knowledge of operating system.
3. Wear labor protection articles as required, and wear qualified protective glasses near the laser beam.
4. Do not process a material before it is clear whether it can be irradiated or heated by laser, so as to avoid the potential danger of smoke and vapor.
5. When the equipment is started, the operator shall not leave the post or entrust someone to be in charge without authorization. If it is really necessary to leave, stop the machine or cut off the power switch.
6. Put the fire extinguisher in an accessible place; Turn off the laser or shutter when not processing; Do not place paper, cloth or other inflammables near unprotected laser beams.
7. In case of any abnormality during processing, stop the machine immediately, eliminate the fault in time or report to the supervisor.
8. Keep the laser, bed and surrounding site clean, orderly and free of oil stain, and stack workpieces, plates and wastes according to regulations.
9. When using gas cylinders, avoid crushing welding wires to avoid electric leakage accidents. The use and transportation of gas cylinders shall comply with the gas cylinder supervision regulations. Do not expose the gas cylinder to the sun or close to the heat source. When opening the bottle valve, the operator must stand on the side of the bottle mouth.
10. High voltage safety regulations shall be observed during maintenance. Maintenance shall be carried out every 40 hours of operation or weekly maintenance, every 1000 hours of operation or every six months in accordance with regulations and procedures.
11. After startup, manually start the machine tool at low speed in X and Y directions to check whether there are abnormalities.
12. After inputting the new workpiece program, it shall be commissioned first and its operation shall be checked.
13. During operation, pay attention to the operation of the machine tool to avoid accidents caused by the cutting machine out of the effective travel range or the collision between the two machines.
5 tips for using aluminum laser cutting machine
1) The double focal length laser cutting head is a vulnerable item on the laser cutting machine. Its long-term use leads to the damage of the laser cutting head.
2) Check the straightness of the track of the fiber laser cutting machine and the verticality of the machine every six months, and timely maintain and debug if any abnormality is found. If this is not done, the cutting effect may not be very good. The error will increase and affect the cutting quality. This is the top priority and must be done.
3) Once a week, use a vacuum cleaner to absorb the dust and dirt in the machine, and all electrical cabinets should be closed to prevent dust.
4) Frequently check the steel belt of optical fiber laser cutting machine to ensure tension. Otherwise, if there is a problem in operation, people may be injured and even die. The steel belt looks like a small thing. The problem is still a little serious.
5) Each guide rail of the optical fiber laser cutting machine shall be cleaned frequently to remove dust and other sundries to ensure the normal operation of the equipment. The rack shall be wiped frequently and lubricated to ensure lubrication without sundries. The guide rail should be cleaned and lubricated frequently, and the motor should also be cleaned and lubricated frequently. The machine can move better and cut more accurately during the travel, and the quality of the cut products will be improved.
Advantages of laser cutting aluminum in construction industry
Laser cutting aluminum is a special machine tool that uses laser technology to cut various graphics on pipe fittings and profiles. It is a high-tech product integrating numerical control technology, laser cutting and precision machinery.
With the characteristics of specialty, high speed, high precision, efficiency and high cost performance, it is the equipment in the non-contact metal pipe processing industry.
So what are its advantages in the construction industry?
1. Laser cutting aluminum has the effectiveness of processing. In today’s era when society focuses on reducing costs and increasing benefits, a new type of equipment is particularly important. Automatic production and computer control have become the advantages of this laser equipment, which can well solve the problems of labor shortage and rising cost.
2. The space control (beam direction change, rotation, scanning, etc.) and time control (on, off, pulse interval) of laser cutting aluminum are excellent and easy to control. In addition, due to the high precision and less burr of laser cutting, the time consumed in subsequent processing is greatly reduced. When changing the diameter or shape of pipe, it only needs to modify the program, so the development of pipe cutting software has research value.
3. Superior performance and long service life. The rigid steel frame structure makes the fuselage very stable, and the unique beam structure ensures the cutting accuracy and speed. Therefore, the laser cutting aluminum injection will become a new favorite in the building materials industry.
4. The accuracy of laser cutting aluminum is much higher. At the same time, as mentioned above, different materials may have small telescopic deformation in the processing process. The pipe laser cutting machine can flexibly adjust according to these deformation, which is not achieved by many traditional processes.
5. Driven by optical fiber laser cutting machine and metal laser cutting machine, due to the low strength of pure aluminum, the tensile strength of laser cutting aluminum is greatly improved by adding a small amount of magnesium, silicon, copper, zinc and other elements. Then, in such a complex and rigorous process, aluminum laser cutting machine has become an important part. It is believed that this aluminum laser cutting machine will also bring infinite vitality to the building materials industry.
What do laser cutting aluminum alloy and stainless steel have in common?
Laser cutting stainless steel
Gas used: nitrogen (it is mainly required that the cutting surface is not oxidized. The thicker the plate, the higher the purity of the gas, generally 99.999%). Of course, when there is no requirement for the cutting surface, oxygen can also be used to cut stainless steel, which is thicker than that when nitrogen is used.
Gas pressure: stainless steel below 10mm, about 10kg. The flow is also large. Nitrogen consumption is large and the cost is relatively high. Above 10mm, needless to say, the pressure, flow and dosage are greater.
Cutting speed: the plate thickness is inversely proportional to the speed. Of course, it is also related to the power of the laser generator.
For example, the speed of cutting 4mm by 4000W laser generator is about 3000-5000mm/min, and the speed of cutting 10mm is about 1000mm /min
Power: it’s hard to say. The manufacturer of laser cutting machine must have a default power. If the cutting is not ideal, the operation can appropriately adjust the power according to the situation (this thing needs to be tried out). Materials from different steel mills may vary)
Focus: the focus position of stainless steel cutting is generally in the middle of the plate thickness.
Laser cutting aluminum
It is more difficult to cut aluminum alloy with laser than SUS. As we all know, one is reflection and the other is high viscosity in melting state.
Generally, air and nitrogen are used. The flow rate should also be 40-50m3/h, and the speed depends on the thickness. It is generally cut up to 12mm. For example, the cutting speed of 6kW laser for 4mm is 4000mm/min, and the cutting speed of 12mm is 700mm/min.
Take reflective protection measures. Please wear a mask when cutting aluminum plate (special reminder).
Figure below: 28mm and 25mm stainless steel, samples cut by laser with high-pressure nitrogen
The above is the relevant knowledge about laser cutting aluminum for you. I hope it can be helpful to you. If you have any ideas, you are welcome to leave your comments in the comments area.