In order to give full play to the role of controlled rolling, it is necessary to strictly control the harmful elements, harmful gases and inclusions in the S355 marine steel plate. Sulfur and phosphorus are very harmful elements for S355 marine steel plate. The content of sulfur and phosphorus in the steel directly affects the plasticity and toughness of the S355 marine steel plate. The presence of second phase particles such as MnS oxide inclusions or carbides will reduce the plasticity and toughness of the S355 marine steel plate and reduce the elongation of the S355 marine steel plate.
Mns has a certain degree of plasticity, which elongates and extends with the rolling direction, which increases the anisotropy of S355 marine steel plate, which is very unfavorable to the transverse performance of S355 marine steel plate. The Fes formed by sulfur causes hot brittle cracks in the hot rolling and welding of S355 marine steel plate. When the sulfur content is high, the H2S corrosion resistance is greatly reduced.
