A steel sheet with a metallic coating is provided. A composition of the metallic coating includes from 2.0 to 24.0% by weight of zinc, from 7.1 to 12.0% by weight of silicon, optionally from 1.1 to 8.0% by weight of magnesium, and optionally additional elements chosen from Pb, Ni, Zr, or Hf. The content by weight of each additional element is less than 0.3%. A balance of the composition is aluminum, unavoidable impurities and residual elements. A ratio Al/Zn is from 4.0 to 6.0.

In a steel sheet for plating, according to one aspect of the present invention, the CBS profile of an Mn element, which is observed in the direction of surface to depth, sequentially comprises local maximum points and local minimum points, difference of converted concentration of Mn can be 10% or higher, and difference of converted concentration of Si can be 10% or higher.

Provided is a hot-dip galvanized steel sheet having excellent low-temperature adhesion and workability, and a manufacturing method therefor, the hot-dip galvanized steel sheet comprising: an inhibition layer formed on a base steel sheet and comprising an FeAl-based intermetallic alloy phase; a hot-dip galvanized layer formed on the inhibition layer; and an AlMn-based alloy phase discontinuously formed between the inhibition layer and the hot-dip galvanized layer.

A hot-dip coated steel substrate coated with a layer of Sn directly topped by a zinc or an aluminum based coating is provided, the steel substrate having the following chemical composition in weight percent:

0.10C0.4%,

1.2Mn6.0%,

0.3Si2.5%,

Al2.0%,

and on a purely optional basis, one or more elements such as

P<0.1%, Nb0.5%, B0.005%,

Cr1.0%,

Mo0.50%,

Ni1.0%,

Ti0.5%,

the remainder of the composition making up of iron and inevitable impurities resulting from the elaboration, the steel substrate further having between 0.0001 and 0.01% by weight of Sn in the region extending from the steel substrate surface up to 10 m.

A process for manufacturing corrosion resistant metal components is disclosed. The process comprises abrasive blasting of a silicon-containing steel substrate followed by hot dip galvanizing, a second abrasive blasting process, treating with a mineral acid, and coating with a polymeric coating. The resulting corrosion resistance is enhanced.

Method for the manufacture of a coated steel sheet including the following successive steps A. the provision of an annealed steel sheet having the following chemical composition in weight: 0.10<C<0.40%, 1.5<Mn<3.0%, 0.7<Si<2.0%, 0.05<Al<1.0%, 0.75<(Si+Al)<3.0%, and on a purely optional basis, one or more elements such as Nb0.5%, B0.005%, Cr1.0%, Mo0.50%, Ni1.0%, Ti0.5%, the remainder of the composition making up of iron and inevitable impurities resulting from the elaboration, such steel sheet being annealed at a temperature between 600 to 1200 C., B. the coating of the steel sheet obtained in step A) with a first coating including nickel, such first coating not including iron, and having a thickness equal or above 0.5 m and C. the coating of the steel sheet obtained in step B) with a second coating based on zinc. A steel sheet, a spot welded joint and further uses of the steel sheet are also provided.

Provided is a galvannealed steel sheet having high strength and excellent deep drawability, and being further excellent in slab cracking resistance and secondary working embrittlement resistance. A base metal steel sheet of the galvannealed steel sheet has a chemical composition containing, in mass %: C: 0.0080% or less; Si: 0.7% or less; Mn: 1.0 to 2.5%; P: more than 0.030 to 0.048%; S: 0.025% or less; Al: 0.005 to 0.20%; N: 0.010% or less; Ti: 0.005 to 0.040%; Nb: 0.005 to 0.060%; and B: 0.0005 to 0.0030%, with the balance being Fe and impurities, satisfying Formula (1) to (4). A galvannealed layer contains 7 to 15 mass % of Fe.
25P+4Si3.6(1)
BX10.0005(2)
C(12/93)NbX20.0035(3)
110Si+48Mn+550P120(4)

Low-density hot dip galvanized steel, comprising a steel substrate (1) located at a core portion and a coating layer (3) located on the surface. An interface layer is disposed between the steel substrate (1) and the coating layer (3), the interface layer comprises an iron particle layer (4), iron particles dispersed on the steel substrate (1) and covering the steel substrate (1) are disposed in the iron particle layer (4), and the iron particles are covered by a first inhibition layer (5). The low-density hot dip galvanized steel contains element Al in a mass percentage of 3.0% to 7.0%. Correspondingly, the present invention also comprises a manufacturing method for the low-density hot dip galvanized steel. The low-density hot dip galvanized steel has a low density, a high strength and high galvanizability and coating layer adhesion.

A coated metallic substrate including at least a first coating consisting of aluminum is provided. The first coating has a thickness between 1.0 and 4.5 m and is directly topped by a second coating based on zinc, such second coating having a thickness between 1.5 and 9.0 m. The thickness ratio of the first coating with respect to the second coating is between 0.2 and 1.2.

A coated metallic substrate including at least a first coating of aluminum, such first coating having a thickness below 5 m and being directly topped by a second coating including from 0.5 to 5.9% by weight of magnesium, the balance being zinc.