(1) Effects of aluminum. Sometimes aluminum is added as a deoxidizer at the time of steelmaking. If the galvanized original plate must use killed steel, a killed steel containing aluminum must be used. However, if the original sheet contains about 0.2% of aluminum, aluminum will accumulate at the grain boundaries, reducing the reactivity of the interfacial reaction. However, aluminum is also easy to enrich on the surface of the steel strip to form oxides and reduce the wettability of the steel plate in the zinc liquid. Therefore, it is generally required that the amount of aluminum contained in the galvanized original plate be controlled at about 0.02%.
(2) Effect of manganese. Manganese is sometimes added to steel as a performance enhancing element. If the original plate contains a certain amount of manganese, and the aluminum content in the zinc liquid is about 0.15%, the effect on the growth of the iron-aluminum compound layer is not significant, but when the aluminum content in the zinc solution is about 0.20%, with the manganese As the content increases, the production of iron-aluminum compound layers decreases. Generally, the manganese content in the original plate is controlled to about 0.25% to 0.40%.
(3) The influence of copper. The copper in the original plate can significantly improve the wear resistance of the galvanized sheet, so when a special purpose corrosion-resistant galvanized sheet is produced, the original sheet having a copper content of 0.2% to 0.3% is often selected. However, copper-containing steel strips may form network defects during hot rolling, are more obvious after pickling, are still visible after cold rolling, and are formed on the surface of the plate in the same direction as the rolling direction after galvanizing, and are similar to thick plate scratches. Scarring of strips or strips. Therefore, the galvanized sheet requires a copper content of not more than 0.15%.
(4) Effect of phosphorus. Phosphorus is a harmful element that is not depleted in steel. Phosphorus also has a significant adverse effect on galvanizing. When the phosphorus content is about 0.15%, the iron-zinc compound layer will become thicker, the pure zinc layer will become thinner, or even there will be no pure zinc layer, and the coating will appear dull. Spots deteriorate the adhesion of the coating. In addition, the steel with high phosphorus content has a large brittleness. In particular, ultra-thin original boards with a thickness of 0.23 mm or less are easily broken when running on a production line. Therefore, the lower the phosphorus content of the galvanized original plate, the better, and the general requirement is less than 0.025%.
(5) The effect of sulfur. Sulfur is also a harmful element that is not depleted in steel. Sulfur has little effect on the galvanizing process, but sulfur seriously affects the mechanical properties of the steel strip. Therefore, the lower the sulfur content, the better. The general requirement is less than 0.03%.
(2) Effect of manganese. Manganese is sometimes added to steel as a performance enhancing element. If the original plate contains a certain amount of manganese, and the aluminum content in the zinc liquid is about 0.15%, the effect on the growth of the iron-aluminum compound layer is not significant, but when the aluminum content in the zinc solution is about 0.20%, with the manganese As the content increases, the production of iron-aluminum compound layers decreases. Generally, the manganese content in the original plate is controlled to about 0.25% to 0.40%.
(3) The influence of copper. The copper in the original plate can significantly improve the wear resistance of the galvanized sheet, so when a special purpose corrosion-resistant galvanized sheet is produced, the original sheet having a copper content of 0.2% to 0.3% is often selected. However, copper-containing steel strips may form network defects during hot rolling, are more obvious after pickling, are still visible after cold rolling, and are formed on the surface of the plate in the same direction as the rolling direction after galvanizing, and are similar to thick plate scratches. Scarring of strips or strips. Therefore, the galvanized sheet requires a copper content of not more than 0.15%.
(4) Effect of phosphorus. Phosphorus is a harmful element that is not depleted in steel. Phosphorus also has a significant adverse effect on galvanizing. When the phosphorus content is about 0.15%, the iron-zinc compound layer will become thicker, the pure zinc layer will become thinner, or even there will be no pure zinc layer, and the coating will appear dull. Spots deteriorate the adhesion of the coating. In addition, the steel with high phosphorus content has a large brittleness. In particular, ultra-thin original boards with a thickness of 0.23 mm or less are easily broken when running on a production line. Therefore, the lower the phosphorus content of the galvanized original plate, the better, and the general requirement is less than 0.025%.
(5) The effect of sulfur. Sulfur is also a harmful element that is not depleted in steel. Sulfur has little effect on the galvanizing process, but sulfur seriously affects the mechanical properties of the steel strip. Therefore, the lower the sulfur content, the better. The general requirement is less than 0.03%.
Corner Bathtub
Corner Bathtub
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