E-grade weather-resistant steel as well as preparation method and application thereof

The invention relates to the technical field of alloy steel, and provides E-grade weather-resistant steel and a preparation method and application thereof.According to the E-grade weather-resistant steel, the content of all chemical elements is limited, innovative technical requirements are put forward, the adding amount of part of key elements is precisely regulated and controlled, and the weather-resistant performance of the E-grade weather-resistant steel is improved. The high-efficiency and easy-to-weld E-grade weather-resistant steel which can meet the requirement of 100 J/cm heat input welding and has the yield strength larger than or equal to 420 MPa, the tensile strength larger than or equal to 540 MPa, the ductility larger than or equal to 19%, the KV2 larger than or equal to 120 J at the temperature of-40 DEG C and the corrosion resistance index I larger than or equal to 6.5 is obtained by exerting the key regulation and control effect of element proportions on the comprehensive performance such as