Abstract: A cold rolled and annealed steel sheet is provided which includes by weight: 0.6<C<1.3%, 15?Mn<35%, 6.0?Al<15%, Si?2.40%, S?0.015%, P?0.1%, N?0.1%, possibly one or more optional elements chosen among Ni, Cr and Cu in an individual amount of up to 3% and possibly one or more elements chosen among B, Ta, Zr, Nb, V, Ti, Mo, and W in a cumulated amount of up to 2.0%, the remainder of the composition making up of iron and inevitable impurities resulting from the elaboration, the microstructure of said sheet comprising at least 0.1% of intragranular kappa carbides, wherein at least 80% of such kappa carbides have an average size below 30 nm, optionally up to 10% of granular ferrite, the remainder being made of austenite, the average grain size and average aspect ratio of the austenite being respectively below 6 ?m and comprised between 2 and 10 and the average grain size and average aspect ratio of the ferrite, when present, being respectively below 5 ?m and below 3.

Abstract: A low density cold rolled and annealed steel sheet having 0.12%?carbon?0.25%, 3%?manganese?10%, 3.5%?aluminum?6.5%, 0%?phosphorus?0.1%, 0%?sulfur?0.03%, 0%?nitrogen?0.1%, 0%?silicon?2%, 0.01%?niobium?0.03%, 0.01%?titanium?0.2%, 0%?molybdenum?0.5%, 0%?chromium?0.6%, 0.01%?copper?2.0%, 0.01%?nickel?3.0%, 0%?calcium?0.005%, 0%?boron?0.01%, 0%?Magnesium?0.005%, 0%?Zirconium?0.005%, 0%?Cerium?0.1%, and the balance including iron, the steel sheet having a microstructure comprising 60% to 90% Delta ferrite, 8% to 30% of residual austenite having average grain size between 0.6 and 2 microns, 1.0% to 10% of alpha-ferrite having average grain size between 0.6 and 2 microns and 0% to 2% of kappa precipitates (Fe,Mn)3AlCx, where x is strictly lower than 1.

Abstract: A cold rolled and annealed steel sheet includes by weight: 0.6?C?1.3%, 15.0?Mn?35%, 5?Al?15%, Si?2.40%, S?0.03%, P?0.1%, N?0.1%, possibly one or more optional elements chosen among Ni, Cr and Cu in an respective amount of up to 4.0%, up to 3.0% and up to 3.0% and possibly one or more elements chosen among B, Ta, Zr, Nb, V, Ti, Mo, and W in a cumulated amount of up to 2.0%, the remainder of the composition making up of iron and inevitable impurities resulting from the elaboration, the microstructure of the sheet including optionally up to 3% of kappa carbides, optionally up to 10.0% of granular ferrite, the remainder being made of austenite, the average grain size and average aspect ratio of the austenite being respectively below 6 ?m and comprised between 1.5 and 6 and the average grain size and average aspect ratio of the ferrite, when present, being respectively below 5 ?m and below 3.0.

Abstract: A rolled steel sheet is provided. The rolled steel sheet has a mechanical strength greater than or equal to 600 MPa and an elongation at fracture that is greater than or equal to 20%. A a method for its fabrication is also provided. The chemical composition of the steel sheet includes 0.10?C?0.30%, 6.0?Mn?15.0%, 6.0?Al?15.0%, and optionally one or more elements selected from among: Si?2.0%, Ti?0.2%, V?0.6% and Nb?0.3%. The remainder of the composition includes iron and the unavoidable impurities resulting from processing. The ratio of the weight of manganese to the weight of aluminum is such that Mn Al > 1.0 . The microstructure of the sheet includes ferrite, austenite and up to 5% Kappa precipitates in area fraction.

Abstract: A cold rolled and annealed steel sheet includes by weight: 0.6?C?1.3%, 15.0?Mn?35%, 5?Al?15%, Si?2.40%, S?0.03%, P?0.1%, N?0.1%, possibly one or more optional elements chosen among Ni, Cr and Cu in an respective amount of up to 4.0%, up to 3.0% and up to 3.0% and possibly one or more elements chosen among B, Ta, Zr, Nb, V, Ti, Mo, and W in a cumulated amount of up to 2.0%, the remainder of the composition making up of iron and inevitable impurities resulting from the elaboration, the microstructure of said sheet comprising optionally up to 3% of kappa carbides, optionally up to 10.0% of granular ferrite, the remainder being made of austenite, the average grain size and average aspect ratio of the austenite being respectively below 6 ?m and comprised between 1.5 and 6 and the average grain size and average aspect ratio of the ferrite, when present, being respectively below 5 ?m and below 3.0.

Abstract: A cold rolled and annealed steel sheet is provided which includes by weight: 0.6<C<1.3%, 15?Mn<35%, 6.0?Al<15%, Si?2.40%, S?0.015%, P?0.1%, N?0.1%, possibly one or more optional elements chosen among Ni, Cr and Cu in an individual amount of up to 3% and possibly one or more elements chosen among B, Ta, Zr, Nb, V, Ti, Mo, and W in a cumulated amount of up to 2.0%, the remainder of the composition making up of iron and inevitable impurities resulting from the elaboration, the microstructure of said sheet comprising at least 0.1% of intragranular kappa carbides, wherein at least 80% of such kappa carbides have an average size below 30 nm, optionally up to 10% of granular ferrite, the remainder being made of austenite, the average grain size and average aspect ratio of the austenite being respectively below 6 ?m and comprised between 2 and 10 and the average grain size and average aspect ratio of the ferrite, when present, being respectively below 5 ?m and below 3.

Abstract: A cold-rolled and annealed ferritic steel sheet is provided. The steel has a composition comprising, expressed by weight: 0.001?C?0.15%; Mn?1%; Si?1.5%; 7.5%?AI?10%; 0.020%?Ti?0.5%; S?0.050%; and P?0.1%. A balance of the composition includes iron and inevitable impurities resulting from the smelting. The structure includes kappa (?) precipitates and equiaxed ferrite, an average grain size d? of the equiaxed ferrite is less than 50 microns, and a linear fraction f of intergranular ? precipitates is less than 30%. The linear fraction f is defined by f = ? ( A ) ? di ? ( A ) ? Li . ?(A)di denotes the total length of grain boundaries containing ? precipitates relative to an area (A) and ?(A)Li denotes the total length of the grain boundaries relative to the area (A). A content of carbon in solid solution is less than 0.005% by weight, and the cold-rolled and annealed ferritic steel sheet has a thickness between 0.6 mm and 1.5 mm.

Abstract: A cold-rolled and annealed ferritic steel sheet is provided. The steel has a composition comprising, expressed by weight: 0.001?C?0.15%; Mn?1%; Si?1.5%; 7.5%?AI?10%; 0.020%?Ti?0.5%; S?0.050%; and P?0.1%. A balance of the composition includes iron and inevitable impurities resulting from the smelting. The structure includes kappa (?) precipitates and equiaxed ferrite, an average grain size d? of the equiaxed ferrite is less than 50 microns, and a linear fraction f of intergranular ? precipitates is less than 30%. The linear fraction f is defined by f = ? ( A ) ? di ? ( A ) ? Li . ?(A)di denotes the total length of grain boundaries containing ? precipitates relative to an area (A) and ?(A)Li denotes the total length of the grain boundaries relative to the area (A). A content of carbon in solid solution is less than 0.005% by weight, and the cold-rolled and annealed ferritic steel sheet has a thickness between 0.6 mm and 1.5 mm.

Abstract: The invention relates to a hot-rolled ferritic steel sheet, the composition of the steel of which comprises, the contents being expressed by weight: 0.001?C?0.15%, Mn?1%, Si?1.5%, 6%?Al?10%, 0.020%?Ti?0.5%, S?0.050%, P?0.1%, and, optionally, one or more elements chosen from: Cr?1%, Mo?1%, Ni?1%, Nb?0.1%, V?0.2%, B?0.010%, the balance of the composition consisting of iron and inevitable impurities resulting from the smelting, the average ferrite grain size dIV measured on a surface perpendicular to the transverse direction with respect to the rolling being less than 100 microns.

Abstract: A rolled steel sheet is provided. The rolled steel sheet has a mechanical strength greater than or equal to 600 MPa and an elongation at fracture that is greater than or equal to 20%. A a method for its fabrication is also provided. The chemical composition of the steel sheet includes 0.10?C?0.30%, 6.0?Mn?15.0%, 6.0?Al?15.0%, and optionally one or more elements selected from among: Si?2.0%, Ti?0.2%, V?0.6% and Nb?0.3%. The remainder of the composition includes iron and the unavoidable impurities resulting from processing. The ratio of the weight of manganese to the weight of aluminum is such that Mn Al > 1.0 . The microstructure of the sheet includes ferrite, austenite and up to 5% Kappa precipitates in area fraction.

Abstract: The invention relates to a hot-rolled ferritic steel sheet, the composition of the steel of which comprises, the contents being expressed by weight: 0.001?C?0.15%, Mn?1%, Si?1.5%, 6%?Al?10%, 0.020%?Ti?0.5%, S?0.050%, P?0.1%, and, optionally, one or more elements chosen from: Cr?1%, Mo?1%, Ni?1%, Nb?0.1%, V?0.2%, B?0.010%, the balance of the composition consisting of iron and inevitable impurities resulting from the smelting, the average ferrite grain size dIV measured on a surface perpendicular to the transverse direction with respect to the rolling being less than 100 microns.