The dissolutive wetting behavior between liquid iron and carbonaceous materials: Experiment and ReaxFF molecular dynamics simulation

Abstract

• The wettability of molten iron on the graphite prism plane is better than that of the graphite basal plane. • The wetting process of molten iron on the graphite basal plane is different from that on the graphite prism plane. • The iron atoms in contact with the incomplete carbon structure will exhibit a cluster structure. • The exfoliation of carbon atoms in the basal model is more complicated than that in the prism model. Understanding the mechanism of the iron-carbon reactive wetting process is very important to understand the interaction between molten iron and carbonaceous materials in the ironmaking process. In this paper, the method of ReaxFF molecular dynamics simulation was used to study the microscopic mechanisms involved in the iron-carbon reactive wetting process. The study examines spreading area, contact angle, microscopic atomic structure, and the interfacial processes. It was found that the wetting process between molten iron and graphite is different for the different crystal orientations of graphite. The wettability of molten iron on the graphite prism plane is better than that on the basal plane. However, the degree of corrosion of molten iron on the graphite basal plane is greater, which is directly related to the way of exfoliation of atoms at different crystal orientation planes. The exfoliation of carbon atoms in the graphite basal model is more complicated, and there are two steps. The iron atoms are in contact with the graphite layer, leading to the formation of defects, which in turn destroy the graphite structure. Then, the iron atoms come into contact with the unsaturated carbon in the pores of the graphite, thereby exfoliating the carbon atoms from the graphitic structure. And the carbon atom exfoliation method in the graphite prism model is relatively simple.