Laser Material Processing

The Welding process

The laser welding turns out us to be a process with high energy density.
A 6 Kw CO₂ Laser Beam, focused by a 200 millimeter focal length converging lens, places to one power density of 10 MW/cm²

To difference of the conventional techniques the welding laser turns out to be an elevated process to energy density that does not only depend on the conditions of conduction of the heat of the material, but is regulated also from the characteristics of the employed laser beam.

CO₂ laser welding

Using a power laser beam two different ways can in fact be used to produce a laser welding process:
•	For low power densities (<10⁶ W/cm²), the laser energy is deposited on the surface of the piece and is transported to the inside by means of a mechanism of heat conduction (conduction welding process).
•	Higher power densities (>10⁶ W/cm²) determine phenomena of ionization as of the piece surface of the metal as of the covering gas from which the formation of a needle cavity, full of ionized metallic and gas vapors (called keyhole), through which the energy deeply penetrates in the material (welding penetration process).

Advantages of the Laser Welding

•	High aspect ratios (Penetration depth and melted width ratio)
•	Very low thermal input energy
•	Job flexibility
•	Easy access to parts to join or weld
•	High mechanical characteristics of the laser weld

Materials

•	Carbon and stainless steels
•	Aluminium and its alloys
•	Nichel and its alloys
•	Titanium and its alloys
•	Copper and its alloys

Last update 10 feb 03

[ Site map ] [ Credits ]