Abstract: A steel sheet hasa chemical composition including in wt % C: 0.2-0.4%, Mn: 0.8-2.0%, Si: 0.1-0.5%, Al: 0.01-0.1%, Ti: 0.01-0.1%, B: 0.0005-0.005%, P?0.040%, Ca?0.01%, S?0.006%, N?0.01%. The steel sheet includes from the bulk to the surface of the coated steel sheet a bulk and a skin layer occupying the outermost 10% of the thickness on either side of the bulk. The bulk includes an inclusion population in which the sum of clustering indexes of MnS and TiN/Ti(C,N) inclusions is less than or equal to 300 ?m/mm2. This allows to manufacture hot pressed parts having a tensile strength equal to or greater than 1300 MPa and a bending anisotropy equal to or lower than 7°.

Abstract: A steel sheet hasa chemical composition including in wt % C: 0.2-0.4%, Mn: 0.8-2.0%, Si: 0.1-0.5%, Al: 0.01-0.1%, Ti: 0.01-0.1%, B: 0.0005-0.005%, P?0.040%, Ca?0.01%, S?0.006%, N?0.01%. The steel sheet includes from the bulk to the surface of the coated steel sheet a bulk and a skin layer occupying the outermost 10% of the thickness on either side of the bulk. The bulk includes an inclusion population in which the sum of clustering indexes of MnS and TiN/Ti(C,N) inclusions is less than or equal to 300 ?m/mm2. This allows to manufacture hot pressed parts having a tensile strength equal to or greater than 1300 MPa and a bending anisotropy equal to or lower than 7°.

Abstract: A steel sheet has a chemical composition including in wt % C: 0.2-0.4%, Mn: 0.8-2.0%, Si: 0.1-0.5%, Al: 0.01-0.1%, Ti: 0.01-0.1%, B: 0.0005-0.005%, P?0.040%, Ca?0.01%, S?0.006%, N?0.01%. The steel sheet includes from the bulk to the surface of the coated steel sheet a bulk and a skin layer occupying the outermost 10% of the thickness on either side of the bulk. The bulk includes an inclusion population in which the sum of clustering indexes of MnS and TiN/Ti(C,N) inclusions is less than or equal to 300 ?m/mm2. This allows to manufacture hot pressed parts having a tensile strength equal to or greater than 1300 MPa and a bending anisotropy equal to or lower than 7°.

Abstract: A press hardened steel part having a composition including, by weight percent: C 0.2-0.34%, Mn 0.50-1.24%, Si 0.5-2%, P?0.020%, S?0.010%, N?0.010%, and including optionally one or more of the following elements: Al: ?0.2%, Cr?0.8%, Nb?0.06%, Ti?0.06%, B?0.005%, Mo?0.35% the remainder of the composition being iron and unavoidable impurities resulting from the smelting. The press hardened steel part has a microstructure including, in surface fraction, 95% or more of tempered martensite and 5% or less of bainite, austenite or ferrite.

Abstract: A method for manufacture of a hot-rolled steel sheet which includes: producing a liquid steel to which manganese, silicon, niobium, and chromium are added, the additions being made in a vacuum chamber, then desulfurizing the liquid metal without increasing its nitrogen content, then adding titanium, said additions being made so as to obtain a liquid metal having a chemical composition where the titanium and nitrogen contents satisfy: Ti/N>3.42, and the carbon, manganese, chromium, and silicon contents satisfy: 2.6C+Mn/5.3+Cr/13+Si/15>=1.1%, then casting a semi-finished product, then heating said semi-finished product to a temperature between 1250° C. and 1300° C. for a holding period at this temperature between 20 minutes and 45 minutes, then hot rolling said semi-finished product to a rolling end temperature TFL between 825° C. and 950° C., to obtain a hot-rolled sheet, then coiling said hot-rolled sheet at a temperature between 500° C. and 750° C.

Abstract: A steel sheet made of a steel having a composition including, C: 0.3-0.4%, Mn: 0.5-1.0%, Si: 0.4-0.8%, Cr: 0.1-1.0%, Mo: 0.1-0.5%, Nb: 0.01-0.1%, Al: 0.01-0.1%, Ti: 0.008-0.03%, B: 0.0005-0.003%, P?0.020%, Ca?0.001%, S?0.004%, N?0.005% and including optionally Ni<0.5%, having a microstructure including, in surface fraction, from 60% to 95% of ferrite, the rest being martensite-austenite islands, pearlite or bainite, and including a bulk and a skin layer occupying the outermost 10% of the thickness on either sides of the bulk, the skin layer having a skin layer inclusion population wherein the surface fraction of oxides is equal to or below 60*10?6.

Abstract: A steel sheet made of a steel having a composition including, C: 0.3-0.4%, Mn: 0.5-1.0%, Si: 0.4-0.8%, Cr: 0.1-1.0%, Mo: 0.1-0.5%, Nb: 0.01-0.1%, Al: 0.01-0.1%, Ti: 0.008-0.03%, B: 0.0005-0.003%, P?0.020%, Ca?0.001%, S?0.004%, N?0.005% and including optionally Ni<0.5%, having a microstructure including, in surface fraction, from 60% to 95% of ferrite, the rest being martensite-austenite islands, pearlite or bainite, and including a bulk and a skin layer occupying the outermost 10% of the thickness on either sides of the bulk, the skin layer having a skin layer inclusion population wherein the cumulated surface fraction of oxides, MnS and TiNbCN is equal to or below 75*10?6.

Abstract: A rolled steel sheet, for press hardening is provided, having a chemical composition where Ti/N>3.42, and the carbon, manganese, chromium and silicon contents satisfy: 2.6 C + Mn 5.3 + Cr 13 + Si 15 ? 1.1 % . The sheet has a nickel content Nisurf at any point of the steel in the vicinity of the surface over a depth ?, such that: Nisurf>Ninom, Ninom denoting the nominal nickel content of the steel, and such that, Nimax denoting the maximum nickel content within ?: ( Ni max + Ni nom ) 2 × ( ? ) ? 0.6 , and such that: ( Ni max - Ni nom ) ? ? 0.01 and the surface density of all of the particles Di, and the surface density of the particles D(>2 ?m) larger than 2 micrometers satisfy, at least to a depth of 100 micrometers in the vicinity of the surface of said sheet: Di+6.

Abstract: A rolled steel sheet, for press hardening is provided, having a chemical composition where Ti/N>3.42, and the carbon, manganese, chromium and silicon contents satisfy: 2.6 C + Mn 5.3 + Cr 13 + Si 15 ? 1.1 % . The sheet has a nickel content Nisurf at any point of the steel in the vicinity of the surface over a depth ?, such that: Nisurf>Ninom, Ninom denoting the nominal nickel content of the steel, and such that, Nimax denoting the maximum nickel content within ?: ( Ni max + Ni nom ) 2 × ( ? ) ? 0.6 , and such that: ( Ni max - Ni nom ) ? ? 0.01 and the surface density of all of the particles Di , and the surface density of the particles D(>2 ?m) larger than 2 micrometers satisfy, at least to a depth of 100 micrometers in the vicinity of the surface of said sheet: Di+6.

Abstract: A rolled steel sheet, for press hardening is provided, having a chemical composition where Ti/N>3.42, and the carbon, manganese, chromium and silicon contents satisfy: 2.6 ? C + Mn 5.3 + Cr 13 + Si 15 ? 1.1 ? % . The sheet has a nickel content Nisurf at any point of the steel in the vicinity of the surface over a depth ?, such that: Nisurf >Ninom, Ninom denoting the nominal nickel content of the steel, and such that, Nimax denoting the maximum nickel content within ?: ( Ni max + Ni nom ) 2 × ( ? ) ? 0.6 , and such that: ( Ni max - Ni nom ) ? ? 0.01 and the surface density of all of the particles Di and the surface density of the particles D(>2 ?m) larger than 2 micrometers satisfy, at least to a depth of 100 micrometers in the vicinity of the surface of said sheet: Di+6.

Abstract: The present invention provides fabrication methods for cold rolled, precoated and press hardened steel sheets, for which the chemical composition includes, with contents expressed by weight, 0.24%?C?0.38%, 0.40%?Mn?3%, 0.10%?Si?0.70%, 0.015%?Al?0.070%, 0%?Cr?2%, 0.25%?Ni?2%, 0.015%?Ti?0.10%, 0%?Nb?0.060%, 0.0005%?B?0.0040%, 0.003%?N?0.010%, 0.0001%?S?0.005%, 0.0001%?P?0.025%, it being understood that the titanium and nitrogen content satisfy: Ti/N>3.42, and that the carbon, manganese, chromium and silicon content satisfy: 2.6C+Mn/5.3+Cr/13+Si/15?1.1%, with the chemical composition optionally including one or more of the following elements: 0.05%?Mo?0.65%, 0.001%?W?0.30%, 0.0005%?Ca?0.005%, with the remainder made up of iron and inevitable impurities coming from preparation.

Abstract: A rolled steel sheet, for press hardening is provided, having a chemical composition where Ti/N>3.42, and the carbon, manganese, chromium and silicon contents satisfy: 2.6 ? C + Mn 5.3 + Cr 13 + Si 15 ? 1.1 ? % . The sheet has a nickel content Nisurf at any point of the steel in the vicinity of the surface over a depth ?, such that: Nisurf >Ninom, Ninom denoting the nominal nickel content of the steel, and such that, Nimax denoting the maximum nickel content within ?: ( Ni max + Ni nom ) 2 × ( ? ) ? 0.6 , and such that: ( Ni max - Ni nom ) ? ? 0.01 and the surface density of all of the particles Di and the surface density of the particles D(>2 ?m) larger than 2 micrometers satisfy, at least to a depth of 100 micrometers in the vicinity of the surface of said sheet: Di+6.

Abstract: The present invention provides a rolled steel sheet, for press hardening, for which the chemical composition includes, with contents expressed by weight, 0.24%?C?0.38%, 0.40%?Mn?3%, 0.10%?Si?0.70%, 0.015%?Al?0.070%, 0%?Cr?2%, 0.25%?Ni?2%, 0.015%?Ti?0.10%, 0%?Nb?0.060%, 0.0005%?B?0.0040%, 0.003%?N?0.010%, 0.0001%?S?0.005%, 0.0001%?P?0.025%, it being understood that the titanium and nitrogen content satisfy: Ti/N>3.42, and that the carbon, manganese, chromium and silicon content satisfy: 2.6 ? C + Mn 5.3 + Cr 13 + Si 15 ? 1.1 ? % , with the chemical composition optionally including one or more of the following elements: 0.05%?Mo?0.65%, 0.001%?W?0.30%, 0.0005%?Ca?0.005%, with the remainder made up of iron and inevitable impurities coming from preparation.

Abstract: The present invention provides a rolled steel sheet, for press hardening, for which the chemical composition includes, with contents expressed by weight, 0.24%?C?0.38%, 0.40%?Mn?3%, 0.10%?Si?0.70%, 0.015%?Al?0.070%, 0%?Cr?2%, 0.25%?Ni?2%, 0.015%?Ti?0.10%, 0%?Nb?0.060%, 0.0005%?B?0.0040%, 0.003%?N?0.010%, 0.0001%?S?0.005%, 0.0001%?P?0.025%, it being understood that the titanium and nitrogen content satisfy: Ti/N>3.42, and that the carbon, manganese, chromium and silicon content satisfy: 2.6 ? C + Mn 5.3 + Cr 13 + Si 15 ? 1.1 ? % , with the chemical composition optionally including one or more of the following elements: 0.05%?Mo?0.65%, 0.001%?W?0.30%, 0.0005%?Ca?0.005%, with the remainder made up of iron and inevitable impurities coming from preparation.

Abstract: The present invention provides a rolled steel sheet, for press hardening, for which the chemical composition includes, with contents expressed by weight, 0.24%?C?0.38%, 0.40%?Mn?3%, 0.10%?Si?0.70%, 0.015%?Al?0.070%, 0%?Cr?2%, 0.25%?Ni?2%, 0.015%?Ti?0.10%, 0%?Nb?0.060%, 0.0005%?B?0.0040%, 0.003%?N?0.010%, 0.0001%?S?0.005%, 0.0001%?P?0.025%, it being understood that the titanium and nitrogen content satisfy: Ti/N>3.42, and that the carbon, manganese, chromium and silicon content satisfy: 2.6 ? ? C + Mn 5.3 + Cr 13 + Si 15 ? 1.1 ? % , with the chemical composition optionally including one or more of the following elements: 0.05%?Mo?0.65%, 0.001%?W?0.30%, 0.0005%?Ca?0.005%, with the remainder made up of iron and inevitable impurities coming from preparation.