Thermoforming steel capable of improving 1800 MPa grade delayed cracking resistance and production method

The invention relates to an improved 1800MPa grade delayed cracking resistant hot forming steel, which comprises the following components in percentage by weight: 0.20 to 0.40 percent of C, 1.30 to 1.70 percent of Si, 0.95 to 1.5 percent of Mn, less than or equal to 0.005 percent of P, less than or equal to 0.003 percent of S, 0.020 to 0.040 percent of A1s, 0.007 to 0.013 percent of Ti, 0.002 to 0.005 percent of B, less than or equal to 0.004 percent of N, 0.025 to 0.040 percent of N, 0.20 to 0.40 percent of Cr and the balance of Fe. The production method comprises molten iron desulphurization; smelting is conducted; performing LF refining; performing RH vacuum treatment; softly blowing argon; casting to form a blank; heating the casting blank; performing finish rolling after conventional rough rolling; coiling after laminar cooling; performing cold rolling after conventional acid pickling; annealing is conducted; blanking is conducted; performing hot stamping forming; and naturally cooling to room temperatur