Effects of pitting corrosion on the void growth of thin steel plates

Corrosion will lead to the serious degradation of the ductile fracture property of thin-walled steel structures because of its small wall thickness. To determine the effects of corrosion pit on the ductile fracture behaviors of thin steel plates, it is necessary to study the ductile fracture microscopic mechanism of corroded thin steel plates. This paper investigated the ductile fracture microscopic mechanism of corroded thin steel plates based on the numerical cubic cell models. A series of computational cubic cell models considering pit depth and shape effects were established. The effects of surface pits depth and shape on microscopic void deformation mechanism in the fracture point of thin steel plates were studied. The ductile fracture criterion of corroded thin steel plates was established according to the micro-voids deformation mechanism, and the average relative error of the nominal fracture strain epsilon n,f calculated by the proposed ductile fracture criterion was 13.62%.