890MPa-grade high-strength steel with low cold crack sensitivity coefficient and production method of 890MPa-grade high-strength steel

The 890MPa-grade high-strength steel with the low cold crack sensitivity coefficient is prepared from the following raw materials in percentage by weight: 0.05 to 0.09 percent of C, 0.12 to 0.60 percent of Si, 1.55 to 1.85 percent of Mn, not more than 0.020 percent of P, not more than 0.010 percent of S, 0.015 to 0.060 percent of Nb, 0.010 to 0.060 percent of Alt, 0.0008 to 0.0025 percent of B, 0.008 to 0.020 percent of Ti, 0.20 to 0.60 percent of Cr, not more than 0.15 percent of Ni, not more than 0.15 percent of Cu, not more than 0.0060 percent of N, not more than 0.0030 percent of O, not more than 0.0002 percent of H, not more than 0.21 percent of Pcm and the balance of Fe and inevitable impurities. According to the 890MPa-grade high-strength steel produced through the production method, the yield strength is larger than or equal to 890MPa, the tensile strength is larger than or equal to 940MPa, the equal-proportion elongation A is larger than or equal to 11%, and the longitudinal impact energy at the temp