The invention discloses a high-strength-
toughness and high-temperature
hot rolled steel plate and a preparation method thereof. The high-strength-
toughness and high-temperature
hot rolled steel plate is prepared from the following chemical components in percentage by weight: 0.04-0.15 percent of C, 0.05-0.35 percent of Si, 0.5-2.5 percent of Mn, 0.005-0.025 percent of Ti, smaller than or equal to 1.0 percent of Cr, smaller than or equal to 0.5 percent of Mo, smaller than or equal to 1.0 percent of Ni, smaller than or equal to 0.5 percent of Cu, smaller than or equal to 0.003 percent of B, smaller than or equal to 0.02 percent of P, smaller than or equal to 0.01 percent of S, smaller than or equal to 0.007 percent of N, 0.001-0.006 percent of O, smaller than or equal to 0.03 percent of the total content of elements including Al, Zr, Mg, Ca and
rare earth and the balance of Fe and inevitable
impurity elements. The preparation method of the steel plate comprises the following steps:
smelting and
casting according to the components, carrying out high-temperature
continuous rolling by adopting an
austenite, carrying out accelerated cooling by watering the steel plate after being rolled, and then
air cooling to
room temperature, wherein the
heating temperature of a steel billet is 1150-1260 DEG, the
cooling temperature is larger than or equal to 5 DEG C / s. and the finish
cooling temperature is 550-650 DEG C . As a microscopic structure of the steel plate is a fined
acicular ferrite type structure, the steel plate is good in strength and
toughness properties. The preparation method of the steel plate is flexible in process and simple in operation, saves the cost and improves the production efficiency.