Assembly Instructions

Ar He N
2
Remarks
Aluminum and alumi-
num alloys
- + - Smooth and polished weld seams are produced with helium or a
helium mix.
The use of argon causes blowholes in the material.
Hydrogen gases cause blowholes in the material.
High-quality weld seams can be produced with carbon dioxide
(CO
2
) or a helium-carbon dioxide mix. However, the weld seams
are less smooth and polished.
Chrome-nickel steel + - + On devices where gas can escape easily, the use of argon is rec-
ommended since it is heavier than nitrogen.
If corrosion is to be avoided under all circumstances, argon must
be used since nitrogen extracts chrome and nickel from the mate-
rial.
Titanium and tita-
nium alloys
+ - - Titanium reacts strongly with the components of air. As long as
the weld cooling down still has a temperature of 200 °C, it is nec-
essary to cover the melting bath completely with argon (e. g. use
of a glove box).
Zircaloy + - - -
Copper - - - Copper must generally be welded without shielding gas. Shielding
gas substantially reduces the incoupling of laser light.
Shielding gas recommended for the material: + = yes, - = no Tab. 2-10
Note
The welding in narrow devices can result in self protection
because the metal vapor displaces the oxygen in the surround-
ings. In such cases, no shielding gas has to be used.
5.4 Shielding gas supply
Shielding gas can be guided to the processing point:
■
via a nozzle
■
via a clamping fixture on the work station.
The following parameters must be optimally adjusted for utiliza-
tion:
■
gas, pure or mix
■
Impact angle
■
Impact range
■
Gas flow
■
Nozzle geometry.
The shielding gas supply must be adapted to the laser device
type (cw or pulsed), welding speed and welding seam.
TRUMPF offers some nozzles as standard supply, which are
described below in more detail.
22-50-17-CRen
2020-01
Using shielding gas
2‐45