The influence of the structural steel grade and galvanizing time on the thickness and surface condition of the applied coatings

The study investigated the influence of the structural steel grade and the hot-dip galvanizing process time on the thickness and surface condition of the zinc coating.The S235, S355 and S460 steels were used for the study.The prepared square-shaped test samples with a thickness of 12 mm were immersed in a zinc bath for 90 s and 150 s.The study showed that a longer zinc bath time increased the thickness of the coating layer.The highest susceptibility to the hot-dip galvanizing process was noted for the S235 steel.The coating with the smallest zinc thickness was obtained for the S355 steel, which was most likely due to the percentage of silicon in the material.Additionally, the study analyzed the surface roughness after the coating process.For all the steels tested, an increase in the roughness of the zinc coating was observed in relation to the raw steel material.However, the researchers did not find any correlation between the surface condition and the thickness of the zinc coating.Hardness tests were also carried out, which showed that the galvanizing time and the type of steel substrate affect the hardness of zinc coatings.