The invention discloses a strong-strength and low-
yield ratio steel plate resistant to
sulfuric acid dew point
corrosion and a manufacturing method for the steel plate. The steel plate comprises the following chemical components in percentage by
mass: 0.06 to 0.10 percent of C, 0.15 to 0.50 percent of Si, 0.90 to 1.20 percent of Mn, less than or equal to 0.012 percent of P, less than or equal to 0.008 percent of S, 0.40 to 0.70 percent of Cr, 0.15 to 0.45 percent of Ni, 0.20 to 0.50 percent of Cu, 0.02 to 0.04 percent of Al, 0.02 to 0.05 percent of V, 0.015 to 0.04 percent of Nb, 0.01 to 0.02 percent of Ti, 0.0005 to 0.005 percent of Ca, less than or equal to 0.007 percent of N and the balance of Fe and inevitable
impurity elements. The steel plate resistant to
sulfuric acid dew point
corrosion is directly manufactured by a
continuous casting billet of 150mm or more, and the manufacturing method comprises the following steps of heating the
continuous casting billet to 1,180 to 1,230 DEG C, preserving heat for 2 to 3 hours, performing rolling after high-pressure water scale removal, cooling the
continuous casting billet to 500 to 620 DEG C at the
cooling speed of 7 to 15 DEG C / s, and performing straightening and cooling to obtain the steel plate resistant to
sulfuric acid dew point
corrosion. According to the steel plate and the manufacturing method, a trace amount of Ca, and Nb and V favorable for improving the
toughness of steel are added on the basis of Cu-Cr-Ni-Ti anticorrosion, and the content of each element is reasonably set, so that the strength and
toughness of the steel are improved on the basis of ensuring the resistance of the steel to the sulfuric acid
dew point corrosion, and the
yield ratio is lowered.