Laser Welding

About Laser Welding

Q1.
What is the feature of YAG laser?
A.

YAG laser is generated when a YAG (yttrium-aluminum-garnet) crystal is excited. A YAG crystal is regarded as one of the most excellent one because it shows various oscillation forms and also presents excellent optical characteristics.

- Transmittable through an optical fiber.
The YAG laser light is transmitted using optical fibers, resulting in easy remote processing and simplified system.
The laser can be set up easily in factory automated system. A single unit offers simultaneous multipoint welding (power-sharing delivery welding) and time-scheduled welding (time-sharing delivery welding) At present, no optical fiber can transmit a high-power CO2 laser light for laser processing.
- Invisible light.
Laser light is near infrared light of 1064 nanometer (1.064 micrometer) wavelength; it is invisible.
- Suitable for micro-processing.
The YAG laser does not diverge but proceeds straight. As the wavelength (1.06μm) is one tenth of CO2 laser wavelength (10.6μm), the YAG laser can be focused to a fine beam, leading to micro-processing.
Q2.
What is the feature of laser welding?
A.

The features of the laser welding are:
Not only metal but also plastic can be laser welded.

  1. Ultra-precision processing.
  2. Less deformation of workpiece owing to non-contact processing.
  3. No electrode is required unlike resistance welding.
  4. Capable of welding different metals, and also non-conductive materials.
  5. No heat distortion owing to short period of joining time.
Q3.
When an optical fiber is replaced with a finer fiber under the same conditions, beam is more focused. Is the density of power increased?
A.
Yes, power density increases. If energy is constant, the smaller the projection area is, the higher the density is; however, you must use caution in the fact that only smaller amount of laser energy can be inputted to smaller area of the end of fiber.