Plate coil for 700MPa-grade high-strength heavy-load automobile carriage plate, production method and application

The invention belongs to the technical field of steel smelting and rolling, and particularly relates to a plate coil for a 700MPa-grade high-strength heavy-load automobile carriage plate, a production method and application, and the plate coil comprises the following components in percentage by weight: 0.08-0.13% of C, 0.10-0.20% of Si, 1.75-1.85% of Mn, less than or equal to 0.015% of P, less than or equal to 0.008% of S, 0.025-0.035% of Als, 0.09-0.11% of Ti, less than or equal to 0.005% of N and 0.057-0.065% of N; the balance is iron element and other inevitable impurity elements; the grain size of the plate coil is 11 grade, the thickness is 4.0-8.0 mm, the tensile strength is 750-755 MPa, the yield strength is 695-705 MPa, the percentage elongation after fracture is 20-21%, and the cold bending property is qualified. By controlling the component proportion of conventional basic elements C, Si, Mn, P and S, controlling main elements such as microalloy Nb and Ti and adjusting, matching and controlling main