A Study on the Adsorption Mechanism and Compactness of the TFS Coating Interfacial Layer

Chrome-plated plates, also known as tin-free plates (TFS), are the latest substrates for coating plates. The coating plate cannot be separated from the TFS during the stamping and extension process, and the interface layer of the TFS coating plate cannot produce pores to ensure good corrosion resistance and the appearance of the metal packaging cans. This requires the TFS coating plate interfacial layer to have good adsorption and compactness. In this paper, the molecular simulation model of the interfacial layer interaction of the TFS coating plate was established by using molecular mechanics simulation, Monte Carlo simulation, and molecular dynamics simulation, and the influential rules of chromium oxide crystalline structure, coating functional group type, and coating pressure on the adsorption and compactness of interfacial layer were analyzed and verified by experiments. The results show that the adsorption is stronger when the surface of the TFS is a chromium oxide (110) crystalline surface and contains hydroxide ions. The adsorption of polyester polyurethane coating and polyether polyurethane coating for and the adsorption of polyester polyurethane coating functional groups is stronger than polyether functional groups, and the adsorption of other functional groups is ranked by the same method. The interfacial layer compactness increases with an increase in coating pressure. For this experimental sample, the value of the film pressure sensor is 18,940 g when meeting the requirements of adsorption and compactness of the interfacial layer of the TFS coating plate, which can be extended for other coating plates.