High-strength medium-carbon low-silicon aluminum cold-rolled dual-phase steel and production method

Abstract

The invention provides high-strength medium-carbon low-silicon aluminum cold-rolled dual-phase steel. The high-strength medium-carbon low-silicon aluminum cold-rolled dual-phase steel is prepared from the following components in percentage by weight: 0.185-0.28% of C, 0.01-0.02% of Si, 1.5-2.5% of Mn, 1.12-1.5% of Cr, 0.2-0.3% of Al, less than 0.005% of S, less than 0.01% of P and less than 0.01% of N. The production method comprises the following production steps: smelting, continuously casting to form a blank conventionally heating the cast blank, and then performing hot rolling on a cast blank; winding; performing cold rolling after conventional acid pickling; annealing before zinc plating; cooling; evenly preserving heat; performing zinc plating; performing air cooling until the temperature reaches a room temperature. According to the production method of the high-strength medium-carbon low-silicon aluminum cold-rolled dual-phase steel, the medium carbon component is combined with low silicon, low manganese and high chromium for alloy compounding strengthening, and therefore, the surface enrichment oxidization degree of the alloy elements can be effectively reduced, the zinc platability of the steel plate can be improved, and the tensile strength of the steel plate is improved to 800MPa and above under the premise of guaranteeing no reduction in automobile safety; as a result, the development requirements on light weight and high strength of automobiles are met.

Description

technical field [0001] The invention relates to a steel for automobiles and a production method, in particular to a high-strength, medium-carbon, low-silicon, aluminum-based cold-rolled dual-phase steel for automobiles and a production method. Background technique [0002] Dual-phase steel is an advanced high-strength steel based on phase transformation strengthening. The microstructure is composed of high-ductility ferrite reinforced tough martensite. The unique microstructure forms the excellent performance characteristics of dual-phase steel in terms of mechanical properties, such as low yield point, high strength, high initial work hardening rate, and good strength and ductility. High strength and work hardening index, low yield ratio and Good bake hardening characteristics and other characteristics have become a new type of stamping steel with high strength and good formability. [0003] Because dual-phase steel combines the requirements of high strength and good forma...

AI Technical Summary

Problems solved by technology

Due to the high content of alloying elements, especially Si and Mn alloys, the surface oxidation is enriched, resulting in the deterioration of the surface quality of galvanized sheets

[0005] In view of the shortcomings of most existing products due to the high content of alloying elements such as Si and Mn, the surface is enriched and oxidized, resulting in poor adhesion of the coating. Laboratory research, on the basis of mechanical properties up to standard, coating adhesion is greatly improved

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