Steel sheet and method for manufacturing same
By controlling the alloy composition and manufacturing process of the steel plate, the area ratio of ferrite and the solid solution Cr content are improved, the cost and corrosion resistance problems caused by high Cr and Cu alloys are solved, and the steel plate manufacturing with high strength and excellent corrosion resistance is achieved.
Patent Information
- Application Number
- CN202380081858.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2022-12-19
- Filing Date
- 2023-12-14
- Publication Date
- 2025-06-24
AI Technical Summary
In the prior art, in order to improve the corrosion resistance and strength of seawater of steel, the use of high content of Cr and Cu alloy elements leads to an increase in cost. At the same time, increasing the fraction of pearlite or bainite will reduce corrosion resistance, making it difficult to find a balance between economy and corrosion resistance.
By controlling the alloy composition and manufacturing process of the steel plate, the area ratio of ferrite in the steel plate is more than 85%, the average grain size is less than 30μm, and the content of solid solution Cr is controlled to be more than 90%. Specific hot rolling and cooling processes are adopted to reduce the fraction of pearlite and bainite, and the corrosion resistance and strength of the steel plate are improved.
Under the premise of economical and high strength, the steel plate has excellent corrosion resistance in seawater environment, the tensile strength reaches more than 600MPa, the impact toughness at -5℃ is more than 100J, and the Cr content of the corrosion product interface after the corrosion test is more than 0.50%, and the relative corrosion rate is less than 60%.