Precision Laser welding Machine
Precision Laser welding Machine
Laser Welding Machine
Lasers can melt and weld metals if sufficiently high irradiance (power per unit area) can be
delivered to small areas on the workpiece surface. Consider an ordinary small pulsed laser
which emits 10 joules of energy in a pulse with a duration of 1 millisecond. With simple optics
it is possible to collect and focus the beam to an area less than 0.01 cm in diameter. This leads
to an irradiance greater than 108
watts/cm2
at the target surface—an extremely high value. It is
much higher than what can be delivered by any conventional light source. It is also considerably
higher than that delivered by almost all other welding sources. For example, an oxyacetylene
torch delivers about 104
watts/cm2
. Only an electron beam machine, which is very large and
requires a vacuum system, can compare to lasers in the ability to deliver such high values of
power per unit area.
Lasers for welding
- Only a few of the many types of lasers that have been developed are useful for welding
applications. The main requirement is that the laser be able to produce sufficiently high levels of
radiant power to melt the material to be welded.
Properties of the laser must be carefully chosen to fit a specific welding application. These
include: - 1. The wavelength of the laser light should be absorbed well by the workpiece.
2. The power available must be high enough to produce melting.
4 Optics and Photonics Series, Photonics-Enabled Technologies: Manufacturing
3. The pulse duration for pulsed lasers must be long enough to permit penetration of heat
into the material.
4. The pulse repetition rate for pulsed lasers must be high enough to weld a seam if seam
welding is required.
Table 1 lists some of the available lasers that have been used for welding. The table also gives
some of the typical values of important parameters that influence the welding. The values given
in the table are an indication of those commercially available, not necessarily the highest values
ever attained