Laser welding machines and laser welding technology is becoming very popular with the advent of the latest laser generation technologies. In short, laser welding is the process of joining metallic bodies or thermoplastics using a laser beam. However, unlike the other conventional welding processes, laser welding can complete the job in much lesser time.
Categorization of Laser Welders
There are multiple modes of laser welding that we can categorize the machines into. Therefore, we can categorize the laser welding technology in various ways. Let’s start defining the laser welding machines by the different categories:
Categorization based on the type of laser.
The pulsed laser mechanism is ideal for the metals that are light in nature and have low thickness. Thus, the pulsed laser makes intermittent exposure on the metallic body. Keeping it safe from burning or melting. Furthermore, this type of laser welding is ideal for welding sheets of metal, razors, jewelry, and even medical prosthetics like screws.
The continuous laser
The continuous laser is ideal for welding on parts that have a high thickness and are strong. Moreover, this welding technology is good for refractory surface metals too. This type of welding is costlier than the pulsed type welding but in the long run, saves a lot of money and labor for you.
Categorization based on the source of laser
Currently, there are three main types of sources of laser for laser welding machines that use one of these laser sources i.e. Fiber laser, CO2 laser, and Nd: YAG laser. Each of these laser sources have their own benefits and are suitable for the different types of welding materials.
Fiber Laser Welding Machine
The fiber laser welding machine is ideal for working on metallic parts. Furthermore, it offers great reliability and efficiency. According to estimates, the accuracy of the laser welding machine using fiber laser is close to 25%.
CO2 Laser Welders
The CO2 laser welders can provide a great continuous welding beam that creates efficient and durable welds. It can easily penetrate metals and non-metallic bodies.
Nd: YAG Laser welders
The Nd: YAG lasers are less energy efficient as compare to the fiber laser welding machines. However, there are certain applications like greater laser control that you cannot achieve with other types of laser sources.
Summing up, you will get laser welders of all types, technologies and sources. You will have to decide which type of laser welder will suit your business the best. Before discussing the selection of the best laser welders, let’s have a look at the main applications of the laser welding machines in the industry.
How Laser Welding Machines Work?
Laser Welding Technology
The laser welding technology works based on the principle of heat generation by the laser source. Sources of laser in the method also vary and different sources of lasers are suitable for different types of materials and their physical and chemical properties. Thus, when the beam of high laser energy is focused on a spot of the metal sheet it creates the metal sheet to melt at the spot. The depth of the hole is managed by the various methods of welding and varies accordingly. This process takes place at the seam of the two metals or materials to be welded together. However, there are multiple methods of laser welding that depend on the type, thickness and quality of materials to be weld.
Laser Welding Methods
There are multiple methods of laser welding that are largely in use in various industries. Let’s discuss some of these laser welding techniques for you to get a better idea of the process of laser welding.
Conduction Mode Welding
Conduction welding is a method that provides you with a wide weld that is shallow. There is a further categorization of this method of welding as follows:
Direct heating method
The direct heating method uses thermal conduction from the source of heat. Subsequently, this results in the melting of the base material and ultimately making the weld with the other material.
Energy transmission method
In comparison, the energy transmission method is slightly different and makes use of an intermediate material that conducts the heat from the source to the weld. Usually, it is the absorbent ink that acts like the intermediary material for the transfer of energy. Similarly, butt joints are also possible by directing the heat energy at an angle of the joint.
- Conduction/Penetration Mechanism
This mechanism works on medium energy and creates deeper hole than the conduction method but shallower than the penetration method.
- Penetration or Keyhole Welding Mechanism
The other way to weld by using a laser is by using the keyhole method. This method focuses the beam of the laser onto the material and creates deep penetration of heat. Thus, a hole is created on the spot by this method. This hole is later filled with metal vapor that forms a bonding material with the other metal. Therefore, the resulting weld makes a great depth to width ration and creates tight welds that are durable.
Applications of Laser Welders
Laser welding finds large applications in various types of industries. These industries range from the manufacturing industry to the medical industry to the jewelry manufacturing industry. Here are a few of the industries that have major applications of laser welding technology.
Robotic welding of parts could never have become a reality if it was not due to the laser welding techniques. The laser beam is aligned on the seam of the parts to be welded. These units are then passed through the laser welding by a conveyor belt. Thus, the speed at which the process happens enables the rapid production of welded products. This technology has applications in an uncountable number of industries. Almost every manufacturing industry that makes use of metallic parts has a use for this kind of welding. Therefore, the application of laser welding is found at large in all types of metallic and non-metallic manufacturing industries that make use of welding of parts.
- Jewelry Industry
Another important application of laser welding is found in the jewelry industry. When you have to make intricate and delicate parts of jewelry from two different materials that are to be weld together, then the best option for welding them together is the laser welding technology.
- Auto-motive Industry
According to twi-global, almost 15% of all the manufacturing processes in the industry involve laser application in one way or another. CO2 type welding has a large application in the automotive industry. The major application of the welding is found in manufacturing of gears, transmission parts, power trains. Most of these products also require circular and annular welds. Thus, the circular welds are also well managed by laser welding.
Furthermore, Nd: YAG has a high application in the welding of body parts and the structure of the automobiles. Laser welding has found large successes in the automotive industry primarily due to the speed of operation, accuracy, efficiency, and lower cost in the long run. You can find out more about the application of laser welding in the automotive industry here.
- Medical Industry
If you start listing down the individual industries that make use of laser welding then you will run out of time and writing space and time but you will not run out of the industries that make use of laser welding. Similarly, the medical industry has a large application of laser welding methods.
The most number of applications of the laser welding technique in the medical industry is the welding of dissimilar metal welding. Medical aids are usually made up of different types of electronic parts that are further fitted with multiple semi-conductors. The main challenge in the scenario arises when the different metals and materials, possessing different chemical and physical properties are to be weld together. But the fiber laser welders do the job successfully.
A few of the hard metals and materials like stainless steel, 440C or 430, and Titanium alloys are also widely in use in the medical industry. These materials are to be weld together with a foolproof system that ensures health of the patient. Other devices like pacemakers, AEDs, drug-pumps also make use of laser welding technologies.
Advantages and Disadvantages of Laser Welding Techniques
Laser welding technology has multiple benefits over conventional types of welding technologies. Here are a few of the advantages that you get by using the laser welding machines.
- The integration of laser welding is easier with automation and Computer Aided Systems. This not only gives you greater control over the entire process but also the operation becomes more accurate and efficient.
- Tools are not affected during the welding process.
- The focus of the laser beam is very accurate. Thus, the final weld is of high quality and durable for a long time to come.
- The speed of the welding process is much higher than that of conventional welding techniques. This makes the laser welding technology suitable for batch productions.
- Laser welding is applicable to products that require a high level of accuracy, like in the manufacturing of medical industry products.
- The input energy is lower than that used in other types of welding techniques.
- No secondary finishing of the product is necessary after welding. Thus, saving the welding time and manpower.
- Contactless method. This means that there are no contacting parts and thus the quality of the final product and the life of the machines will be better.
Things to look out for during Laser Welding
Although there are no disadvantages of laser welding per se. However, there are a few things that need to be taken care of while applying the method on an industrial scale.
It is understandable that laser welding requires a certain amount of skill to accomplish the task. In case if the task is accomplished by someone who is not aware of the laser welding technique then the final product will suffer.
A few of these incidents where lack of technique or experience comes into play are as follows:
- Clear understanding of the job and the type of laser to use is a must for the technician working on the laser welding system.
- Removing air pockets is a must for the technicians. If the air pockets will stay during the welding process then the weld will not be durable and fail after a little time. This problem mostly arises in the pulse laser welding method.
- Application of the laser heat evenly along the surface of the metal during the laser conduction welding method is a must. If the laser heat will not distribute evenly along the surface, it might result in uneven welds, which will create reliability issues in the future.
- You have to be extra-cautious when welding on optical surfaces as they can get damaged easily.
Furthermore, the initial investment involved in laser welding machines is relatively higher than other welding methods. In addition, the maintenance cost of the machine is also higher if it develops issues during operation.
Laser Welding Certification
Certification courses are on offer by multiple universities around the world. These certifications are to certify that the certificate holder has a specific level of knowledge and hands-on practice with the technology. Here are the main types of certifications available for the technical staff:
LWTSP: Laser Working Technical Support Provider
This certification is ideal for support staff that is responsible for setting up and calibration of the laser machines. Thus, this certification also covers the technical aspects and minor repair of the machines if they fail during operation.
LWP: Laser Working Professional
This certification is for the laser welding professional. Especially, for the ones who are actively in the designing and engineering of laser welding in any capacity.
These are just of the types of certifications that you and your staff can get for starting laser welding technology in your business.
Laser Welding Systems: Final Word
Summing up, we hope that you have enjoyed the multipronged information on laser welding that we have compiled for you. Our team of experts’ at HeatSign is here to resolve any of your queries if you want to ask us. We specialize in all types of laser technologies and will guide you to perfection. All you have to do is contact us and we will be available to provide assistance to you.