Low-cost high-strength structural steel plate Q460D and manufacturing method

The invention relates to a low-cost and high-strength structural steel plate Q460D and a manufacturing method, and belongs to the technical field of metallurgy. 0.10% to 0.30% of Si; mn: 1.20% to 1.70%; less than or equal to 0.025% of P; s is less than or equal to 0.010%; 0.020% to 0.040% of Alt (aluminum nitride); the content of V is 0.030 to 0.070 percent; 90 to 120 ppm of N; and the balance of Fe and inevitable trace impurities. A continuous casting billet obtained after smelting and continuous casting are conducted on the components is reheated, the reheating temperature ranges from 1050 DEG C to 1150 DEG C, rough rolling is conducted with the thickness 2.5-3.5 times of the thickness of a finished product, finish rolling is conducted with the controlled rolling thickness 2.0-2.5 times of the thickness of the finished product, the controlled rolling temperature ranges from 900 DEG C to 950 DEG C, and the finish rolling temperature ranges from 850 DEG C to 900 DEG C; and the rolled finished product is subje