Audi A8 D5 - Laser Soldering;Brazing; Replacement Joining Techniques in Repair Work (Steel)

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with respect to the correctness of information in this document. Copyright by AUDI AG.
For information on the relevant renewal procedure, refer to the
corresponding chapter ( ⇒ page 29 or ⇒ page 30 ).
It is essential to refer to the Workshop Manual for the relevant
vehicle in such cases.
The laser welding technique employs a high-energy light beam
directed onto the weld seam by means of optical lenses or fibre
optics. During the welding process the upper panel is fused onto
the partially molten lower panel, creating a welded joint both with
and without additional material.
6.7 Laser soldering/brazing
Note
This joining technique is only used during the manufacture of the
vehicle.
For information on the relevant renewal procedure, refer to the
corresponding chapter ( ⇒ page 29 or ⇒ page 30 ).
It is essential to refer to the Workshop Manual for the relevant
vehicle in such cases.
A filler material is always used when performing laser soldering/
brazing. In most respects, the soldered/brazed joint is no different
from an MIG brazed joint.
The only difference is that the filler material is melted on using a
concentrated light beam (similarly to laser welding), rather than
an arc. This laser technique enables the energy to be used pre‐
cisely where it is needed. Unwanted side effects such as thermal
distortion are negligible.
6.8 Replacement joining techniques in re‐
pair work (steel)
In production For repair measures
Spot welding Spot-weld bonding /
MAG plug-welding /
MAG welding
MAG welding MAG welding
MIG soldering/braz‐
ing
MAG welding
Laser welding MAG welding
Laser soldering/
brazing
MIG soldering/brazing (not approved for
AUDI AG vehicles)
Bonding
MAG welding
Note information in Workshop Manual
Bonding Bonding / MAG welding
Spot-weld bonding Bonding with spot welding / additional
weld spots / additional MAG welding
Pop riveting Pop rivets
Only use pop rivets specified in Workshop
Manual.
As a rule, commercially available pop riv‐
ets do not provide sufficient strength.
General InformationBody Repairs, General Body Repairs - Edition 04.2018
6. Thermal joining techniques 29