High-strength and high-fatigue-performance steel plate and preparation method thereof

The invention particularly relates to a high-strength and high-fatigue-performance steel plate and a preparation method thereof, and belongs to the technical field of steel preparation, relatively simple component design is adopted, C, Si, Mn, Cr, Nb, Ti and other conventional alloy elements are adopted, Cr, Mo and other elements are added, the hardenability of the material is guaranteed, more hard phases are obtained, and the strength is guaranteed; the low-carbon component design is adopted, and elements such as Nb and V are added, so that refined grains of the material are obtained, and the yield strength and fatigue strength of the material are guaranteed; by adding Cu, Ni and other elements, the corrosion resistance of the steel plate is guaranteed, the yield strength of the finished steel plate is 900-950 MPa, the tensile strength is 950-1050 MPa, the percentage elongation after fracture is 3-6%, the yield ratio is larger than or equal to 0.9, the fatigue strength is larger than or equal to 850 MPa (the