Entwicklung hoher Zinkauflagen auf kontinuierlich feuerverzinktem Breitband

The production of continuously hot-dip galvanized strip with a zinc coating of more than 600 g/m² and strip widths of more than 800 mm leads to the formation of characteristic defects in different areas of the zinc coating. The aim of this work is to investigate those defects and to identify and limit the causes for their development. In order to gain a basic knowledge of the equipment used and the complex production parameters involved, a detailed literature study is carried out at the beginning. This research concerns the metallurgical fundamentals, the process used to adjust the coating thickness and various mathematical models and simulations representing the strip galvanizing process. In addition, a comparison of the errors already known and investigated in the literature with the existing ones is to be made. To counteract these phenomena, the relevant defects will be systematically investigated and further a test program will be developed after the evaluation of the data obtained. This program is intended to illustrate the influence of the surface quality of the starting material on the quality of the metal coating on the final product. The subsequent investigations include the metallographic evaluation of specimens under the light microscope as well as under the scanning electron microscope. In addition, various parameters such as surface roughness on the starting material and zinc coating thickness on the end product are measured. With these data and the observations from the production tests carried out, it is possible to isolate the causes of defects for both phenomena investigated.