EH36-grade steel plate and preparation method thereof

The invention provides an EH36-grade steel plate which comprises the following components in percentage by mass: 0.07-0.1% of C, 0.15-0.25% of Si, 1.55-1.65% of Mn, less than or equal to 0.01% of P, less than or equal to 0.003% of S, 0.012-0.02% of Ti, less than or equal to 0.005% of N, less than or equal to 0.005% of O, less than or equal to 0.00002% of H, less than or equal to 0.01% of Al, 0.0002-0.0035% of Ca, less than or equal to 0.035% of V, 0.0005-0.001% of B and the balance of Fe and inevitable impurities. The carbon equivalent Ceq of the steel plate is controlled to be 0.33-0.39; the maximum welding line energy of the steel plate is 400 kJ/cm, and the thickness of the steel plate is larger than or equal to 60 mm. The invention further provides a preparation method of the EH36-grade steel plate. According to the preparation method of the EH36-grade steel plate provided by the invention, the prepared EH36-grade steel plate can bear welding input heat of 400kJ/cm, and the thickness of the EH36-grade ste