Weldable low-alloy high-strength steel and preparation method and application thereof

The invention relates to weldable low-alloy high-strength steel and a preparation method and application thereof.According to the weldable low-alloy high-strength steel and the preparation method thereof, by controlling material components, the specific element ratio and the preparation method, on the basis of controlling the material cost, the weldable low-alloy high-strength steel is high in strength, weldable and good in mechanical property matched with strength and toughness; meanwhile, the weldable low-alloy high-strength steel has good hydrogen embrittlement resistance; the weldable low-alloy high-strength steel is good in hydrogen environment embrittlement resistance in a high-pressure hydrogen environment and excellent in obdurability, the tensile strength of 800 MPa or above and low hydrogen embrittlement sensitivity are guaranteed, meanwhile, welding is easy, the welding process is simple, site construction can be achieved, and the weldable low-alloy high-strength steel is suitable for industrial pr