A coated metallic substrate is provided, including, at least; one layer of oxides, such layer being directly topped by an intermediate coating layer comprising Fe, Ni, Cr and Ti wherein the amount of Ti is above or equal to 5 wt. % and wherein the following equation is satisfied: 8 wt. %<Cr+Ti<40 wt. %, the balance being Fe and Ni, such intermediate coating layer being directly topped by a coating layer being an anticorrosion metallic coating.

A hot-dip-coated, non-skin-passed, cold-rolled metal strip is provided. The metal coating of the metal strip includes a waviness Wa.sub.0.8 of less than or equal to 0.70 μm, 0.2 to 8% by weight of aluminum and magnesium, and up to 0.3% by weight of additional elements, the balance being zinc and inevitable impurities. Metal parts are also provided.

A hot-dip-coated, non-skin-passed, cold-rolled metal strip is provided. The metal coating of the metal strip includes a waviness Wa.sub.0.8 of less than or equal to 0.70 μm, 0.2 to 8% by weight of aluminum and magnesium, and up to 0.3% by weight of additional elements, the balance being zinc and inevitable impurities. Metal parts are also provided.

An Al-steel assembly is provided. The assembly includes an aluminum-based element and a steel element on at least one surface of the aluminum-based element. The steel element has a metal coating made of a zinc-aluminum-magnesium alloy and includes from 2.3% to 3.3% by weight of magnesium and from 3.6% to 3.9% by weight of aluminum. A coated surface of the steel element is in contact with the aluminum-based element in an assembly zone and a protective coating coats the assembly around and adjacent the assembly zone. A body-in-white, further assembly and method are also provided.

An Al-steel assembly is provided. The assembly includes an aluminum-based element and a steel element on at least one surface of the aluminum-based element. The steel element has a metal coating made of a zinc-aluminum-magnesium alloy and includes from 2.3% to 3.3% by weight of magnesium and from 3.6% to 3.9% by weight of aluminum. A coated surface of the steel element is in contact with the aluminum-based element in an assembly zone and a protective coating coats the assembly around and adjacent the assembly zone. A body-in-white, further assembly and method are also provided.

A hot-dip galvanized steel sheet includes a plated layer formed on at least a part of a surface of a steel sheet, the plated layer containing: Al in a range from 10 mass % to 40 mass %; Si in a range from 0.05 mass % to 4 mass %; Mg in a range from 0.5 mass % to 4 mass %; and the balance consisting of Zn and inevitable impurities. The plated layer has a lamellar structure in which a layered Zn phase and a layered Al phase are alternately arranged in a cross section of the plated layer, the lamellar structure accounting for 5% or more by an area fraction in the cross section, and a total abundance ratio of an intermetallic compound containing at least one of Fe, Mn, Ti, Sn, In, Bi, Pb or B is regulated to 3% or less by the area fraction.

A hot-dip galvanized steel sheet includes a plated layer formed on at least a part of a surface of a steel sheet, the plated layer containing: Al in a range from 10 mass % to 40 mass %; Si in a range from 0.05 mass % to 4 mass %; Mg in a range from 0.5 mass % to 4 mass %; and the balance consisting of Zn and inevitable impurities. The plated layer has a lamellar structure in which a layered Zn phase and a layered Al phase are alternately arranged in a cross section of the plated layer, the lamellar structure accounting for 5% or more by an area fraction in the cross section, and a total abundance ratio of an intermetallic compound containing at least one of Fe, Mn, Ti, Sn, In, Bi, Pb or B is regulated to 3% or less by the area fraction.

A high-strength steel sheet comprises: a chemical composition containing C, Si, Mn, P, S, Al, N, Mo, Cr, Ca, and Sb with a balance consisting of Fe and inevitable impurities, wherein [% Si], [% Mn], [% P], [% Mo], and [% Cr] satisfy a predetermined relationship; a steel microstructure that contains ferrite, hard phase, and retained austenite and in which a carbon concentration in the retained austenite is 0.55% or more and 1.10% or less, an amount of diffusible hydrogen in the steel sheet is 0.80 mass ppm or less, a surface layer softening thickness is 5 μm or more and 150 μm or less, and a corresponding grain boundary frequency in a surface layer of the steel sheet after a high-temperature tensile test is 0.45 or less; and a tensile strength of 980 MPa or more.

A high strength cold rolled steel sheet has a composition which contains, in terms of mass %, more than 0.15% and not more than 0.45% of C, 0.50-2.50% of Si, 1.50-3.00% of Mn, not more than 0.050% of P, not more than 0.0100% of S, 0.010-0.100% of Al and not more than 0.0100% of N, with the remainder including Fe and unavoidable impurities, has a total content of ferrite and bainitic ferrite of 20-80%, has a retained austenite content of more than 10% and not more than 40%, has a martensite content of more than 0% and not more than 50%, and is such that the proportion of retained austenite that has an aspect ratio of not more than 0.5 is not less than 75%, and the proportion of retained austenite having an aspect ratio of not more than 0.5 that is present at Bain group boundaries is not less than 50%.

An object is to provide a high strength steel sheet having a TS (tensile strength) of 980 MPa or more and excellent formability and a method for manufacturing the steel sheet.

A high strength steel sheet which is excellent in terms of formability, which is manufactured under optimized manufacturing conditions, and which has a predetermined chemical composition and a steel microstructure including, in terms of area fraction, 35% or more and 80% or less of ferrite, 5% or more and 35% or less of as-quenched martensite, 0.1% or more and less than 3.0% of tempered martensite, and 8% or more of retained austenite, in which the average grain size of the ferrite is 6 μm or less, in which the average grain size of the retained austenite is 3 μm or less, in which a value calculated by dividing the average Mn content in the retained austenite by the average Mn content in the ferrite is 1.5 or more, in which a value calculated by dividing the sum of the area fraction of as-quenched martensite having a circle-equivalent grain size of 3 μm or more and the area fraction of retained austenite having a circle-equivalent grain size of 3 μm or more by the sum of the area fraction of all the as-quenched martensite and the area fraction of all the retained austenite is less than 0.4, and in which a value calculated by dividing the area fraction of retained austenite grains adjacent to three or more ferrite grains having different crystal orientations by the area fraction of all the retained austenite is less than 0.6.