Molecular dynamics simulation on the corrosion characteristics of iron in liquid lead

The corrosion characteristics of the iron in the liquid lead have been studied by applying molecular dynamics method with generalized embedded atom method (GEAM). According to the obtained results, as the temperature rises, the surface atom of the iron bulk is progressively stripped by the liquid lead, which results in the gradual decrease of the total number of body-centered cubic (BCC) crystal units of the iron. The stripped Fe atoms diffuse with low ratios but can deeply into the interior of the lead. Conversely, the Pb atoms penetrate at high ratios but hardly into the interior of the iron. Additionally, the Fe atoms mainly diffuse into the Pb side, while just a few Pb atoms penetrate into the Fe side. The distribution of the Fe and Pb atoms at the interfacial area is in disorder. Furthermore, the thickness of the interfacial region gradually increases with the increasing temperature. The roughness of the contact surface has a significant impact on the corrosion process of the iron in the lead. The rough surfaces can aggravate the corrosion of the iron. Finally, the predominant diffusion mechanism of Fe atom in the lead is the interstitial and the first-nearest neighbor (1 NN) hopping mechanism. The aforementioned conclusions can perfect the understanding of the corrosion problem and the use of the liquid lead in engineering. (C) 2018 Elsevier Ltd. All rights reserved.