In this work, the tinplate with 0.5 g·m−2 tin coating mass was prepared in order to improve the economic benefit for food packaging field. We studied this low Sn-coated steel surface state and developed a process combined Mo-Mn-Al-P coating based on its special structure. By Taguchi techniques optimization, this chromium-free multi-elements coating has excellent corrosion resistance and adhesion with organic coatings, would be a hopefully replacing traditional chromate passivation treatment on tinplate with low tin coating mass.

The influence of electrodeposition coating uniformity is complex. In essence, coating thickness depends on the potential distribution on cathode surface, which is jointly affected by geometric factors and electrochemical factors. In a practical high-speed tin plating production process, the existence of edge effect has always been an important problem to the homogeneity of electrodeposition coatings. Due to the complexity of production equipment and high costs of spot experiments, modeling and simulation have become a promising method for studying how to improve the uniformity of coatings. In this paper, we proposed reasonable model simplification strategies in high-speed tin electrodeposition process and studied the influence of anode arrangement and auxiliary equipment to the uniformity of tin plating coating based on COMSOL Multiphysics. The results showed that simply changing the relative positions of cathode and anode cannot make the coating evenly distributed, while adding specific auxiliary devices at appropriate locations would helpfully solve the uneven coating problem caused by edge effects. This research not only aims at high-speed tin plating system, but also has a great reference with any plate-type cathode electrodeposition for improving the homogeneity of coatings.