Abstract: The present invention discloses a seawater-corrosion-resistant steel, the mass percentage of the chemical elements thereof being: 0.03-0.05% of C, 0.04-0.08% of Si, 0.8-1.2% of Mn, 0.1-0.2% of Cu, 2.5-5.5% of Cr, 0.05-0.15% of Ni, 0.15-0.35% of Mo, 1.5-3.5% of Al, 0.01-0.02% of Ti, 0.0015-0.003% of Ca, and the balance being Fe and other inevitable impurities. The present invention further discloses a method for manufacturing the seawater-corrosion-resistant steel. The method includes the following steps: (1) smelting and casting; (2) reheating: reheating a casting blank to 1200° C.-1260° C.; (3) rough rolling; (4) finish rolling; (5) coiling; and (6) cooling to room temperature. The seawater-corrosion-resistant steel has good seawater corrosion resistance and excellent mechanical properties.

Abstract: A steel for high-strength aluminum clad substrate, comprising the following chemical elements by mass percent: C: 0.008-0.02%, 0<Si?0.005%, Mn: 0.25-0.5%, P: 0.018-0.03%, Al?0.005%, N: 0.0040-0.010%, Ti: 0.02-0.04%, O: 0.02-0.050%, and the balance being Fe and other inevitable impurities. The manufacturing method therefor comprises the steps of: (1) smelting and casting; (2) reheating: reheating a casting blank to 1180° C.-1250° C.; (3) rough rolling; (4) finish rolling; (5) coiling; and (6) cooling to room temperature. The steel for high-strength aluminum clad substrate has good strength and good plasticity.

Abstract: There is disclosed in the disclosure a protective steel plate with excellent cold roll formability, comprising: three soft steel layers (1, 4, 5) and two hard steel layers (2, 3), wherein the three soft steel layers (1, 4, 5) and the two hard steel layers (2, 3) are positioned alternately, and face layers of the protective steel plate are soft steel layers (1, 4, 5), wherein the hard steel layers (2, 3) and the soft steel layers (1, 4, 5) are atomically bonded by rolling cladding; wherein the soft steel layers (1, 4, 5) comprise chemical elements in percentage by mass of: C: 0.001-0.01%, 0<Si?0.005%, Mn: 0.05-0.15%, 0<Al?0.005%, Ti: 0.01-0.10%, with a balance of Fe and other unavoidable impurities.

Abstract: There is disclosed in the disclosure a protective clad steel plate, comprising hard steel layers (1, 3, 5) and soft steel layers (2, 4) arranged alternately, wherein face layers of the protective clad steel plate are hard steel layers (1, 3, 5), wherein the hard steel layers (1, 3, 5) and soft steel layers (2, 4) are atomically bonded by rolling cladding; wherein the soft steel layers (2, 4) comprise chemical elements in percentage by mass of: C: 0.001-0.01%, 0<Si?0.005%, Mn: 0.05-0.15%, 0<Al?0.005%, Ti: 0.01-0.10%, with a balance of Fe and unavoidable impurities.

Abstract: The invention provides a highly corrosion-resistant, high strength, Al-containing weathering steel plate, wherein the chemical composition comprises in weight percentages (wt %) of: C: 0.02-0.07%, Si: 0.2-1.0%, Mn: 0.2-2.2%, P?0.01%, S?0.006%, Cu: 0.2-0.5%, Cr: 0.5-3.5%, Ni: 0.2-1.2%, Al: 0.4-4.0%, N?0.005%; selectively added one or more of Nb: 0.01-0.06%, Ti: 0.01-0.10%, V: 0.02-0.10%; the balance of Fe and unavoidable impurities, wherein Al/Cr is 0.5-8.0. The steel plate has a yield strength of 350-500 MPa, an elongation of 20% or more, a relative corrosion rate of 27% or less and a good impact toughness and a low yield ratio. The present application also provides a method for manufacturing the weathering steel plate.

Abstract: There is disclosed in the disclosure a protective clad steel plate, comprising hard steel layers (1, 3, 5) and soft steel layers (2, 4) arranged alternately, wherein face layers of the protective clad steel plate are hard steel layers (1, 3, 5), wherein the hard steel layers (1, 3, 5) and soft steel layers (2, 4) are atomically bonded by rolling cladding; wherein the soft steel layers (2, 4) comprise chemical elements in percentage by mass of: C: 0.001-0.01%, 0<Si?0.005%, Mn: 0.05-0.15%, 0<Al?0.005%, Ti: 0.01-0.10%, with a balance of Fe and unavoidable impurities.

Abstract: There is disclosed in the disclosure a protective steel plate with excellent cold roll formability, comprising: three soft steel layers (1, 4, 5) and two hard steel layers (2, 3), wherein the three soft steel layers (1, 4, 5) and the two hard steel layers (2, 3) are positioned alternately, and face layers of the protective steel plate are soft steel layers (1, 4, 5), wherein the hard steel layers (2, 3) and the soft steel layers (1, 4, 5) are atomically bonded by rolling cladding; wherein the soft steel layers (1, 4, 5) comprise chemical elements in percentage by mass of: C: 0.001-0.01%, 0<Si?0.005%, Mn: 0.05-0.15%, 0<Al?0.005%, Ti: 0.01-0.10%, with a balance of Fe and other unavoidable impurities.

Abstract: The invention provides a highly corrosion-resistant, high strength, Al-containing weathering steel plate, wherein the chemical composition comprises in weight percentages (wt %) of: C: 0.02-0.07%, Si: 0.2-1.0%, Mn: 0.2-2.2%, P?0.01%, S?0.006%, Cu: 0.2-0.5%, Cr: 0.5-3.5%, Ni: 0.2-1.2%, Al: 0.4-4.0%, N?0.005%; selectively added one or more of Nb: 0.01-0.06%, Ti: 0.01-0.10%, V: 0.02-0.10%; the balance of Fe and unavoidable impurities, wherein Al/Cr is 0.5-8.0. The steel plate has a yield strength of 350-500 MPa, an elongation of 20% or more, a relative corrosion rate of 27% or less and a good impact toughness and a low yield ratio. The present application also provides a method for manufacturing the weathering steel plate.