Development of a methodology to evaluate corrosive creepage using a survival and reliability analysis model

Abstract

The subject of this work is the development of a method for the evaluation of corrosive creeping according to the survival and reliability analysis. To realize this goal, steel sheets with four types of coatings were scratched and exposed to a corrosive alternating climate test (VDA 233–102) until they reached a selected value for severity of corrosion which is defined as infiltration of (U/2) ≥ 2 mm. The time to reach this defined target is noted and mathematical modeling of the data, on the basis of survival and reliability models, was performed. The investigation, according to survival analysis, with variable dwell and fixed infiltration values, makes it possible to get predictions of the severity of corrosion. Using this evaluation methodology, it is possible to get additional information on the corrosion protection system under research. The additional information includes: the speed of corrosion in mm/day, the initiation time, and the propagation gradient.