Abstract
Keywords:
Perforation corrosion, Hemming joint, Pitting corrosion, Automotive body, Sealants, Galvannealed coated steel, Cyclic corrosion test
Abstract
The hemming and lapped parts in automotive body are easy to stagnate water and pollutants, which can include very corrosive elements such as chloride, acid solution depending on the circumstance. These cause the pitting corrosion easily. However, it is very difficult to predict the expected life span of those parts because corrosion mechanism is very complicated, and several factors exist such as the design of lapped parts, humidity, and temperature and so on. This paper describes a corrosion characteristic of hemming joints according to the application of anticorrosion subsidiary materials - hemming and white sealant - on the cold-rolled and galvannealed coated steel. The experiment was carried out in a cyclic corrosion test (CCT) machine. It also discusses about the anticorrosion life of hemming joints on the basis of the correlation between CCT data and actual vehicles, and it would help us predict the anticorrosion life for lapped parts of automobiles.