The application discloses a large
liquid carbon dioxide ship low-temperature steel plate and a preparation method thereof, and belongs to the field of steel
metallurgy. The main chemical components of the steel plate are C, M, Si, Ni, Ni+Cu+Cr, Nb, Al, Ti, Nb+Al+Ti, S, P, and the rest are Fe and inevitable
impurity elements. The clean steel
smelting process is adopted to prepare a large-thickness
continuous casting billet with high purity and high homogenization. The fine quasi-polygonal ferrite+
acicular ferrite+
carbide-free
bainite structure is obtained through low-temperature large reduction (
compression ratio greater than or equal to 7) hot mechanical
coupling rolling+two-stage controlled rolling and controlled cooling. The large
liquid carbon dioxide ship low-temperature steel plate is produced by adopting the TMCP process, has the advantages of large thickness, high strength, -60 DEG C CTOD and the like, meets the construction requirements of the large
liquid carbon dioxide ship with low temperature and low pressure, has the advantages of simple manufacturing process, short production period and low
alloy cost, and will greatly promote the large-scale development of the liquid
carbon dioxide ship.