What is a laser?
A laser is a device that generates an intense beam of coherent monochromatic light through the stimulated emission of photons by an excited atom or molecule. The word laser is an acronym for Light Amplification by Stimulated Emission of Radiation (LASER).
The laser has various applications such as holography, barcode reading, surgical procedures, playing or recording media on CD’s, drilling, cutting and welding. Lasers also find applications in military operations as they can be used as weapons or in security systems. The most common use for these beams is in the industrial sector though, for cutting, drilling and welding.
Laser beam welding is a technique used to join multiple pieces of metal with the use of a focused laser beam. The laser beam provides a concentrated heat source that helps in creating narrow and deep welds. The laser welding process is often used in high volume applications such as the manufacturing of cars and other automotive parts.
The process of laser welding is based on the penetration or keyhole mode of welding. Laser welding has a variety of types that are used for different applications. These types include:
- Plastic welding
- Heat conduction welding
- Spot and seam welding
- Hybrid welding
- Laser metal deposition
- Deep welding
- Scanner welding
Though the method of welding may differ the basic principle of laser welding remains the same.
How is laser welding done?
Laser welding can be achieved through two methods. The method depends on the radiation intensity of the laser. The two methods are:
- Conduction Welding
In this laser welding process, the power densities of the laser beam are low and the heat is transferred through conduction. The laser does not completely penetrate the material and is only absorbed close to the surface. The heat melts the metal at the point where the workpiece is to be joined. The melted metal flows together and solidifies to form a permanent weld. The welding depth for this process is generally very low, which makes the process ideal for welding parts that have thin walls.
- Keyhole Welding
During this process, the laser beam penetrates the material to form a keyhole in the workpiece. The keyhole is also called a steam capillary as some of the metal is vaporized to form metal steam. This capillary is surrounded by melted metal that flows around it and solidifies at the point where the weld is to be made. The welding depths and the power densities of the laser for this process are generally high.
The laser welding process has various advantages not only in the manufacturing industry but even in other industries such as the medical industry, fashion industry and the electronics industry. We list some of these benefits below.
A major benefit of laser welding is that it provides a high level of control and accuracy. The precision of the welding process enables it to weld the smallest parts together without causing them any damage.
- High strength welding
The welding done with the laser welding process is extremely robust and high-quality. No filler materials are required during this process, which increases the strength of the welds.
- Complicated joints
Another major advantage of laser welding is that it can create complicated joints and reach areas that are difficult to reach with traditional techniques. With laser welding, you can even weld parts made from different materials without causing any damage to the parts.
- Repeatable welding
The same type of weld can be consistently replicated with this process, making welding of mass-produced parts easier. Laser welding is faster and more versatile than other traditional welding techniques.
- Low heat application
Laser welding requires low heat and causes less thermal strain on the components being welded. The use of localised energy allows for a contact-free application and minimises the distortion of the workpiece.
Laser welding has become popular in various industries recently due to its various advantages and applications. An application of laser welding is battery welding that is used most commonly for the welding of PCBs and heat sensitive components. We at Mikro Innotech offer customized solutions for the various applications of laser welding.