High-strength Q630GJ steel plate and production method thereof

The invention discloses a high-strength Q630GJ steel plate and a production method thereof. A V-Ni-Nb-Ti microalloy component design is adopted by the steel plate. The steel plate is prepared from the following microalloy chemical components in percentage by weight: 0.04%-0.045% of V, 0.35%-0.45% of Ni, 0.02%-0.03% of Nb and 0.015%-0.025% of Ti. The production method comprises a rolling procedure and a thermal treatment procedure. Through reasonable component design, controlled rolling and cooling and a low-temperature tempering process, the high-strength steel plate with good mechanical property is obtained. According to the steel plate, the tissue is tempered ferrite+martensite+bainite, the yield ratio is smaller than or equal to 0.83, the maximal thickness of the steel plate is 80mm and the localization of the tempered high-strength steel plate with low yield ratio is achieved. 本发明公开了种高强度Q630GJ钢板及其生产方法，所述钢板采用V-Ni-Nb-Ti微合金成分设计，所述微合金化学成分及质量百分含量为：V：0.04～0.045%，Ni：0.35～0.45%，Nb：0.02～0.03%，Ti：0.015～0.025%。生产方法包