1 Series E81 130i (N52K) 3-door
Elasticity is only 1/3 as high.
Elongation failure is approx. 50% slighter.
Convertibility is limited in comparison
with steel.
Overstretching the material results in
strain-hardening and an increased
tendency of cracking.
Electrical conductivity is almost 4 times higher.
Electric welding procedures require
different equipment (MIG welding).
Material expansion during heating is twice as high.
The material expands more markedly.
Shorter heat treatment is necessary for
removing dents.
Thermal conductivity is 3 times higher.
Heat is drained more quickly. Adjoining
working areas are affected more heavily
e.g. during welding.
Microstructural change between 200
°
C and 250
°
C.
Elongation characteristics and thus
plasticity are improved.
Strength is reduced.
Important!
No heat treatment when working
on the vehicle structure!
Temperature cannot be
monitored to sufficiently exact
levels in garages.
Aluminum shows no annealing colors.
The melting point is 650
°
C. Once the
melting temperature has been reached,
the material begins to flow without any
further indications.
The temperature can only be estimated
by means of the paint coloring and the
surface warpage.
Important!
Do not use thermal applicators.
Not suitable for garage use
because the paint runs too
quickly.
1.4 Mounting
Characteristic features of aluminum
Special measures
Corrosion (ageing) in damp environments.
Store aluminum parts in a dry place.
Contact corrosion in event of contact e.g. with steel parts.
Always store aluminum parts separately
or in isolation from steel parts.
Susceptibility to paint infiltration.
Do not damage protective surface layer
since this would cause oxidation.
RA Materials science
BMW AG - TIS
22.01.2013 06:21
Issue status (12/2007) Valid only until next DVD is issued
Copyright
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