Production method for producing two types of 590MPa-grade DH steel of continuous annealing and zinc plating by using same raw materials

The invention relates to the technical field of metallurgy, in particular to a production method for producing continuous annealing 590MPa-grade DH steel and galvanized 590MPa-grade DH steel by using the same raw materials, which comprises the following steps: preparing an intermediate product cold hard steel coil through the steps of steelmaking, hot rolling and acid rolling, and then respectively carrying out a continuous annealing process or a continuous annealing-galvanizing process, and the chilled steel coil is processed into two types of products, namely 590MPa-grade continuous annealing DH steel or 590MPa-grade galvanized DH steel. The steel billet comprises the following chemical components in percentage by weight: 0.12%-0.15% of C, 0.30%-0.50% of Si, 1.5%-1.7% of Mn, 0.4%-0.6% of A1, 0.010%-0.018% of Nb, and Plt is limited; 0.012%, Slt; 0.005%, Nlt; 0.003%, with the balance being Fe and inevitable impurities. Raw material chemical components, early-stage production processes and intermediate product