Abstract
There are two typical of corrosion occuring in the areas of the world where automobilies are most susceptable to corrosion. One is charactarized as inside-out perforation corrosion caused by salty or muddy water entering places that do not dry readily, such as panel joints and the inner surfaces of closed structures. Another is characterized as cosmetic corrosion caused by paint chipping damage to outer panel surfaces or damage resulting from interference between parts.
Since the anti-corrosion warranty period for automobilies is expected to be further extended in the years ahead, there is a need to estabilish a life prediction method, based on the use of accelerated corrosion tests, which will allow performance evaluations to be completed in a shorter period.
This paper describes an optimized accelerated test procedure for evaluating the anti-corrosion life of body panels. It also discusses the inside-out perforation and cosmetic corrosion resistance of a Zn-Ni electro-plated steel sheet with a thin organic film, which has been developed on the basis of the results obtained with the optimized test procedure.
