Flat steel product with metallic cover and method for its manufacture

摘要

The flat steel product comprises a metallic coating applied on a base layer (St) that is made of a steel material, where the main component of the coating is zinc. In the metallic coating, three layers are stamped, two of which is partially alloyed with one another. The thickness of the coating is limited to 3.5 mu m. A first layer is formed in the coating. A second zinc layer (Zn) that contains 80 wt.% of zinc and a third layer are optionally formed in the coating. The coating is optionally coated with a plasma polymer layer. The first layer is an aluminum-zinc layer. The flat steel product comprises a metallic coating applied on a base layer (St) that is made of a steel material, where the main component of the coating is zinc. In the metallic coating, three layers are stamped, two of which is partially alloyed with one another. The thickness of the coating is limited to 3.5 mu m. A first layer is formed in the coating. A second zinc layer (Zn) that contains 80 wt.% of zinc and a third layer are optionally formed in the coating. The coating is optionally coated with a plasma polymer layer. The first layer is an aluminum-zinc layer, which contains 60 wt.% of zinc and 50 wt.% of aluminum. The first layer has a maximum thickness of 1000 nm. The second zinc layer has a thickness of 3.3 mu m. The third layer has a maximum thickness of 600 nm. A transition area, in which the layers are gradiently alloyed into each other, is formed between the third layer and another layer of the coating adjacent to it and has a maximum thickness of 1500 nm. The thickness of the plasma polymer layer lying on the coating is 1500 nm. An independent claim is included for a method for producing a flat steel product.