TRIP-added high-strength steel for hot-dip galvanizing and production method thereof

The invention belongs to the field of metallic materials, and particularly relates to TRIP-added high-strength steel for hot-dip galvanizing and a production method thereof. The TRIP-added high-strength steel for hot-dip galvanizing provided by the invention is composed of the following chemical components by mass percent: 0.16-0.20% of C, 1.1-1.2% of Al, 0.6-0.8% of Mn, 0.06-0.08% of P, 0.03-0.05% of Si, 0.05-0.07% of Nb, 0.19-0.21% of Mo, 0.19-0.21% of Cr and the balance of Fe. The production method comprises the following steps: carrying out first-stage austenite single-phase area rolling on a billet, then carrying out second-stage two-phase area high reduction rolling, quickly cooling, cooling and pickling a hot rolled plate, carrying out cold rolling on the hot rolled plate for multiple passes, carrying out heat preservation on the hot rolled plate at a high temperature for a short period of time, slowly cooling a bainite area, carrying out heat treatment and carrying out hot-dip galvanizing in a zinc pot. By adopting the production method, selective oxidation in continuous annealing and galvanizing processes can be greatly reduced, the platability of the TRIP-added high-strength steel is improved, and the strength and ductility product of the TRIP-added high-strength steel is ensured to be higher than 20GPa%.