Brochure Coil Coatings - BASF Coatings

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Substrates
Form, function and variety
It doesn’t matter whether it’s for washing machine housings, a roof covering or a façade element. Flat rolled metal
from a steel or aluminium mill is the basis of countless industrially manufactured products. More than 20 million
tonnes of steel are coated annually around the world using the coil coating process. Additionally 2 million tonnes or
so of aluminium and other substrates are coated. The later application is a key factor in determining which material
is processed in which form.
Choice of substrate
Which substrate is the right one for
a particular application is decided on
the basis of various criteria. The
further machining stages, for example,
the coated metal has to undergo,
have to be taken into account when
selecting the substrate. Roll forming,
bending and deep-drawing each
require a particular material strength
and grade. The coated product’s
field of use – whether indoors or
outdoors, as a structural element or
in a transport operation – also plays
a key role in selecting the substrate.
Steel – strong, durable,
universally usable
Steel boasts a long service life,
universal applicability and good
recycling properties. The material
properties can be adapted to a wide
range of applications by means of
alloys or thermal and mechanical
treatment. Cold rolled steel offers
the following fundamental options
for further processing:
Sheet steel which is not further
treated is mainly used indoors –
i.e. for products which are rarely
exposed to aggressive influences
and are thus less at risk of
corrosion, such as lights.
Refined sheet steel is either
hot-dip galvanised or electrogalvanised
(using zinc, magnesium,
aluminium or an alloy of these)
and is the most frequently used
substrate in coil coating. The
resulting products, such as façade
and roof elements, withstand
outdoor climatic exposure very
well – and meet extremely
stringent specifications in terms
of weather and corrosion resistance
and service life.
Aluminium – light, versatile
and flexible
Aluminium is comparable to steel in
many regards – for example, with
reference to its durability, its varied
applications and its recyclability.
Although it may not be as strong as
steel, it is two-thirds lighter. Aluminium
is therefore often used in aviation
and other transport applications,
and it is also very popular with
architects. The selection of special
alloys allows the mechanical
properties of aluminium – for instance,
hardness and deep-drawability – to
be specifically adapted to the desired
product features.