Method for producing low-alloy high-strength steel based on headless thin slab casting and rolling process

The invention provides a method for producing low-alloy high-strength steel based on a headless thin slab casting and rolling process. The method comprises the steps of selecting raw materials, wherein the raw materials comprise, by mass, 0.04%-0.06% of C, 0.10%-0.30% of Si, 0.6%-1.0% of Mn, no more than 0.025% of P, no more than 0.010% of S, 0.020%-0.040% of Alt, 0.01%-0.02% of Ti, 0.020%-0.030%of Nb, no more than 0.005% of N and the balance Fe; smelting the raw materials in a converter, a RH furnace and an lF in sequence; and enabling molten steel formed in the LF pass an ESP production line to produce hot rolled strips with different thicknesses, wherein the temperature of a rough rolling inlet is no lower than 950 DEG C, the temperature of an induction heating outlet is 1100 DEG C-1190 DEG C, the temperature of a finish rolling outlet is 830 DEG C-900 DEG C, and the coiling temperature is 560 DEG C-620 DEG C. With the method provided by the invention, the problems of low extensibility and weldability and