A kind of 1000mpa grade alloyed hot-dip galvanized composite phase steel and preparation method thereof

Abstract

The invention relates to 1000 MPa grade alloyed hot-dip galvanized complex phase steel and a preparation method thereof, and belongs to the technical field of iron and steel smelting. The alloyed hot-dip galvanized complex phase steel comprises following chemical components including 0.08%-0.11% of C, 0.2%-0.6% of Si, 2.1%-2.6% of Mn, smaller than or equal to 0.01% of P, smaller than or equal to 0.01% of S, 0.1%-0.3% of Al, 0.2%-0.5% of Cr, 0.1%-0.4% of Mo, 0.03%-0.06% of Ti, 0.03%-0.05% of Nb and the balance Fe and inevitable impurities. A metallographic structure comprises ferrite, bainite and martensite, and has a reinforcement precipitated phase. The alloyed hot-dip galvanized complex phase steel has the tensile strength larger than 1000 MPa, the yield ratio is low, elongation reaches14%, the hole expansion rate reaches 69%, and good flanging and hole expanding performance, forming performance and welding performance are achieved.

Description

technical field [0001] The invention belongs to the technical field of iron and steel smelting, and in particular relates to a 1000MPa grade alloyed hot-dip galvanized multi-phase steel and a preparation method thereof. Background technique [0002] In recent years, with the development of the automobile industry and the need for energy saving and emission reduction, improving the safety of the vehicle and reducing the weight of the vehicle body have become the main trend of the development of the automobile industry. In order to cope with this trend, some automakers in Europe, America and other countries have adopted more and more aluminum alloy and carbon fiber materials on newly released high-end models to achieve the purpose of improving safety and reducing weight. It should be pointed out that aluminum alloy and carbon fiber materials are expensive and not suitable for family economical cars. Therefore, more and more high-strength steels are used in body-in-white manufa...

AI Technical Summary

Problems solved by technology

However, for auto parts with flanging and reaming requirements, due to its structural characteristics, a large number of reaming cracks occur in the actual use of dual-phase steel, which is difficult to meet the design requirements

In actual production, the alloying process needs to heat the hot-dip coated strip steel to a certain temperature for alloying reaction, so maintaining the stability of the structure at this temperature has also become a difficult point. In addition, when the hot-dip coated strip steel is too high or Too low aluminum content in the zinc solution will lead to too slow or too fast reaction of the alloy coating, seriously affecting the quality of the coating

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