Laser Beam Welding - LBW

Reasons to Adopt the Laser Welding Process

laserwelding — Fri, 17 Jul 2009 22:05:36 +0000

Laser Beam Welding, commonly known as LBW, is an extremely adaptable welding process that’s able to weld many different materials. Laser welding titanium, stainless or carbon steel, and aluminum are all commonly done. This process can provide and extremely high quality weld and easily weld very thin materials with little to no distortion in the parts. There is one adverse effect that can happen though, and that’s cracking in the weld. This is caused by the rapid cooling that can often occur in a laser welding piece.

Another reason for choosing the laser welding process is that it’s very suitable for a production environment. Since it’s capable of welding a wide range of thicknesses, the power input can easily be adjusted to account for almost any type of metal used with this process. Not only does this aid in the selection metals to be welded, the speed with which the metals can be welded can be varied merely by changing the power output from the laser.

One of the great advantages of the laser welding process versus the electron beam welding process, is that it can be accomplished without the need for a vacuum - It’s possible to transmit a laser beam through the air. Combine that with the ease of automation and you can begin to see why laser welding may be the best choice for your application. Not only that, but with the potential for automation it’s highly likely that you’ll be able to reduce your costs when you factor in the cost savings due to decreased manpower involved.

So if you’ve got a very difficult material to weld, or a very thin section that needs to be welded with little to no distortion, or if you need to automate your welding process and need high cycle speeds, laser welding is often the best solution.

A Little About Laser Welding

laserwelding — Fri, 17 Jul 2009 21:38:09 +0000

Laser Welding is similar to electron beam welding in that it has a large power density. It was developed in order to provide a welding process that had both high cooling and heating cycle rates and a small HAZ – heat affected zone. Power outputs of around 1 megawatt per square centimeter are the norm.

The area of the weld can typically be as small as 0.2 mm or as large as 13 mm. In most laser welding processes though, the size of the weld tends to be on the lower end of the scale. By controlling the power of the beam, and the focal length of the laser beam, the characteristics of the weld can be easily and tightly controlled. Incidentally, better welds are often achieved by fixing the focus point of the laser beam so that it is a little bit below the weld materials surface. The reason for this is that it greatly improves penetration of the laser welding beam.

Since there are many types of welding needs and requirements, there arises a need to have different laser welding processes. The two primary types of laser welding are what is known as a pulsed beam, or a continuous beam. As you can probably gather from the names, a continous beam laser implies that the beam operates continuously, whereas a pulsed beam laser means that it’s pulsed on and off.

Each of these types is more suited to certain welding applications. For instance, a pulse beam laser welder can easily control the heat input to the welded metal. By varying the on and off time of the laser, it’s quite easy to weld very thin sections of metal with little to no distortion.

Conversely, for thicker sections of metal, a continuous beam laser will be able to provide enough power to penetrate the complete thickness of the material, which will help to provide complete fusion.