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Corrosion
4. Corrosion
This chapter gives a brief overview about
corrosion, with a main focus on specific
aspects of high strength material where
powder- and gas actuated fastener are
4.1 Different forms of corrosion
Depending on the environmental conditions and material, different forms of corrosion will
occur.
1. Homogeneous corrosion
Homogeneous material reduction
Most of the commonly observed material
degradation can be traced back to this corrosion
form, characterized by a more or less
homogeneous surface reduction. This form
of corrosion is not of big importance for
DX- / GX-fasteners.
The amount of material loss due to corrosion
can be approximated in laboratory scale
experiments. The so-called corrosion rate is
generally listed as mm/year or g/m 2 h (laboratory
values). The mean corrosion rate of
low alloyed steel and zinc, for example, is
shown in following table.
made of. More details on corrosion are
described within the Hilti corrosion brochure
“Corrosion Resistant Fastenings, Edition
May 2000”.a prerequisite (e.g. water).
A = starting level
B = reduction of the thickness due to homogeneous
corrosion
K = grain (crystal), the structure is determined by a
large number grains
Atmosphere Mean surface removal / year
zinc coatings low alloyed steel
(dechema handbook)
rural 1– 2 µm 10– 60 µm
town 3– 5 µm 30– 70 µm
industrial 6–10 µm 40–160 µm
marine 5– 9 µm 60–230 µm
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