HIGH-STRENGTH CAR PART WITH CORROSION-RESISTANT COATING AND METHOD OF ITS MANUFACTURING Russian patent published in 2018 - IPC C23C28/00 C25D7/06 

FIELD: motor vehicle industry.

SUBSTANCE: invention relates to a high-strength car component with a corrosion-resistant coating and a method for its manufacturing. Said part comprises a molded steel sheet having on its surface a layer of an intermetallic Al-Fe compound with a thickness of at least 10 mcm and not more than 50 mcm, layer of the surface coating disposed on the said Al-Fe intermetallic compound layer surface including a comprising ZnO coating, and a zinc phosphate coating and having a surface roughness of at least 3 mcm and not more than 20 mcm as the maximum height of the Rt profile value in accordance with the Japanese industry standard JIS B0601 (2001), and an electrodeposited paint film disposed on the said surface coating layer surface and having a thickness of at least 6 mcm and not more than 15 mcm. High-strength car component with a corrosion-resistant coating manufacturing method includes the aluminum coating application onto the steel sheet, surface coating containing ZnO layer application onto the aluminum-coated steel sheet surface, conducting of the said steel sheet hot pressing, and application of the galvanized precipitated paint film with a thickness of at least 6 mcm and not more than 15 mcm. ZnO content in said surface coating layer is at least 0.3 g/m² and no more than 3 g/m² in the metallic zinc equivalent for one surface of the aluminum coated steel sheet. Heating prior the hot pressing is carried out at a temperature increase rate of not less than 12 °C/s with the steel sheet maximum temperature of not less than 870 °C and not more than 1,100 °C.

EFFECT: enabling the car part having improved corrosion resistance, improved formability with hot pressing, and an improved chemical conversion capacity after hot pressing.

25 cl, 3 dwg, 2 tbl, 1 ex