In the framework of an extensive test program established by the Automotive Applications Committee of the American Iron and Steel Institute, Hoogovens took part with its newly developed accelerated cyclic corrosion test.
Objective of this program is to develop a reliable laboratory accelerated test for cosmetic corrosion resistance in order to obtain a realistic ranking of automotive steel sheet products.
A number of standard treated steel sheet products were tested in the new cyclic test including cold-rolled steel, hot-dip galvanised steel and electroplated zinc and zinc-nickel. Also included was a second phosphate system for cold-rolled steel and hot-dip galvanised steel.
Results of the test are given in terms of paint creep from the scribe and blistering along the scribe.
It is concluded that the new test discriminates well between relatively “good” and “bad” materials. It appears that precoating is not always beneficial in lowering undercutting.
However, the appearance of the samples (red rust, white rust) also plays an important role in the assessment of the results as to application of materials in the automotive industry.