Laser welding is a process used to join metal pieces together. A beam provides a concentrated heat source, which results in narrow, deep welds. This type of process is used frequently in the automotive industry. |
There are some advantages to using this process instead of electronic beam:
- The beam can be transmitted through the air instead of requiring a vacuum. - It is easy to incorporate into robotic machinery - It does not generate x-rays - Higher quality welds
There are two main types of lasers used in this process: solid-state and gas. Whichever material is used, the result emits photons to form the beam.
In this process, a solid medium (rather than a liquid one) is used to generate the beam. It usually has a glass or crystalline material, to which an element such as neodymium, chromium, erbium, or ytterbium is added. A common combination is synthetic ruby and neodymium in glass.
When laser welding with this process, operators must wear special eyewear or use special screens to prevent damage to the eyes. Some types can operate with a pulsing or continuous beam, and others only use the pulsed beam. Pulses are typically used to weld thin materials such as razor blades. A continuous beam is used for deeper welds.
Originally, many of these were rod-shaped crystals with flat ends surrounded by a flash tube that contained xenon or krypton. The flash emitted a pulse lasting about two milliseconds. This model is still popular today, but more efficient types such as disk-shaped crystals and diodes are now becoming more prevalent.
Gas types use mixes of gases as a medium. Typical gases include helium, nitrogen, and carbon dioxide. A high-voltage, low-current power source supplies the energy to excite the gas mixture. This gives the lasting medium used for the beam. It can operate in a continuous or a pulsed mode. Because of the added power of this type, they are especially useful for high-volume applications.
Regardless of the method used, the beam has to be moved to the seam being welded. In a traditional type, a person or a robot actually moves the laser beam to follow along the seam. Most modern applications, however, use a remote method in which the beam is moved along the seam by a scanner. This is a much faster and more precise method.
Laser welding offers a variety of methods for any joining job. The process used will depend on the type of metal and the specific application.
For quality laser welding services, visit Joining Technologies, Inc. Learn more at http://www.joiningtech.com/pages/welding.html#laser.
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