Abstract: A process for producing a steel product having a protective coating based on zinc and a tribologically active layer applied to the protective coating where the process includes providing a flat steel product provided with the protective coating, and applying an aqueous solution comprising ammonium sulfate and demineralized water to the protective coating of the steel product. The concentration of the ammonium sulfate based on the SO42? ions is 0.01-5.7 mol/L, the pH of the aqueous solution is 4-6, and the near-surface reaction time between the aqueous solution and the protective coating is more than 0 seconds and not more than 5 seconds. After a drying operation conducted without preceding rinsing, a tribologically active layer consisting of ammonium zinc sulfate is formed atop the protective zinc coating. Also, a steel product having a protective coating based on zinc and a tribologically active layer of ammonium zinc sulfate.

Abstract: A method is disclosed which allows a tribologically optimally effective coating to be produced on a steel product surface provided with a Zn-based protective coating using simple products which are nonhazardous with respect to environmental pollution. For this purpose, a correspondingly coated flat steel product is provided, and an aqueous solution consisting of an ammonium sulfate and completely desalinated water is deposited onto the protective coating of the steel product. The concentration of the ammonium sulfate in the aqueous solution is 0.01-5.7 mol/l and the pH value of the aqueous solution is 4-6 with respect to the SO42? ions. At same time, the reaction time near the surface between the aqueous solution and the protective coating is more than 0 seconds and maximally 5 seconds such that a tribologically active layer which consist of ammonium zinc sulfate is provided on the protective coating after a drying process which is carried out without an upstream flushing process.

Abstract: Coating materials with minimized lubricant demand enable optimized tribological conditions in forming flat steel products and are also unobjectionable in relation to their effects on the environment. With such coating materials, steel components can be produced by forming flat steel products in forming machines. For example, a tribologically-active layer may be produced on at least one surface of a flat steel product or a forming machine used to form the flat steel product, wherein the at least one surface comes into contact with the opposing component during forming. The tribologically-active layer may be formed by coating the at least one surface with a coating material from a group consisting of aluminum sulfate, ammonium sulfate, iron sulfate, and magnesium sulfate. The flat steel product may be inserted into the forming machine to be formed into the steel component.

Abstract: Coating materials with minimized lubricant demand enable optimized tribological conditions in forming flat steel products and are also unobjectionable in relation to their effects on the environment. With such coating materials, steel components can be produced by forming flat steel products in forming machines. For example, a tribologically-active layer may be produced on at least one surface of a flat steel product or a forming machine used to form the flat steel product, wherein the at least one surface comes into contact with the opposing component during forming. The tribologically-active layer may be formed by coating the at least one surface with a coating material from a group consisting of aluminum sulfate, ammonium sulfate, iron sulfate, and magnesium sulfate. The flat steel product may be inserted into the forming machine to be formed into the steel component.