Abstract: A steel part having a homogeneous multiphase microstructure in each region of the part, the microstructure containing ferrite, wherein the steel part is obtained by a process involving: cutting a blank from a strip of steel, having a specified composition; optionally, the blank undergoes prior cold deformation; the blank is heated to reach a soak temperature Ts above Ac1 but below Ac3 and held at this soak temperature Ts for a soak time ts adjusted so that the steel, after the blank has been heated, has an austenite content equal to or greater than 25% by area; the heated blank is transferred into a forming tool to hot-form the part; and the part is cooled within the tool at a cooling rate V such that the microstructure of the steel, after cooling the part, is a multiphase microstructure containing ferrite and being homogeneous in each region of the part.

Abstract: A steel part having a homogeneous multiphase microstructure in each region of the part, the microstructure containing ferrite, wherein the steel part is obtained by a process involving: cutting a blank from a strip of steel, having a specified composition; optionally, the blank undergoes prior cold deformation; the blank is heated to reach a soak temperature Ts above Ac1 but below Ac3 and held at this soak temperature Ts for a soak time ts adjusted so that the steel, after the blank has been heated, has an austenite content equal to or greater than 25% by area; the heated blank is transferred into a forming tool to hot-form the part; and the part is cooled within the tool at a cooling rate V such that the microstructure of the steel, after cooling the part, is a multiphase microstructure containing ferrite and being homogeneous in each region of the part.

Abstract: The subject of the invention is a process for manufacturing a part made of steel having a multiphase microstructure, said microstructure comprising ferrite and being homogeneous in each of the regions of said part, which process comprises the steps consisting in: cutting a blank from a strip of steel, the composition of which is typical of that of steels having a multiphase microstructure; said blank is heated so as to reach a soak temperature Ts above Ac1 but below Ac3 and held at this soak temperature Ts for a soak time ts adjusted so that the steel, after the blank has been heated, has an austenite content equal to or greater than 25% by area; said heated blank is transferred into a forming tool so as to hot-form said part; and said part is cooled within the tool at a cooling rate V such that the microstructure of the steel, after the part has been cooled, is a multiphase microstructure, said microstructure comprising ferrite and being homogeneous in each of the regions of said part.

Abstract: The invention relates to a process for manufacturing a part having very high mechanical properties from a hot-rolled or cold-rolled steel strip, comprising precoating said strip with aluminum or an aluminum alloy, cold deformation of the coated strip, possible cutting of the excess sheet with a view to the final geometry of the part, heating of the part so as to form an intermetallic compound from the steel/precoat interface and to austenitize the steel, transfer of the part to a tool and cooling of the part in the tool at a rate such that the steel has, after being cooled, a martensitic or bainitic structure or a martensite-bainite structure. The precoating is carried out by electroplating, by chemical or physical vapor deposition or by co-rolling.

Abstract: The subject of the invention is a process for manufacturing a part made of steel having a multiphase microstructure, said microstructure comprising ferrite and being homogeneous in each of the regions of said part, which process comprises the steps consisting in: cutting a blank from a strip of steel, the composition of which is typical of that of steels having a multiphase microstructure; said blank is heated so as to reach a soak temperature Ts above Ac1 but below Ac3 and held at this soak temperature Ts for a soak time ts adjusted so that the steel, after the blank has been heated, has an austenite content equal to or greater than 25% by area; said heated blank is transferred into a forming tool so as to hot-form said part; and said part is cooled within the tool at a cooling rate V such that the microstructure of the steel, after the part has been cooled, is a multiphase microstructure, said microstructure comprising ferrite and being homogeneous in each of the regions of said part.

Abstract: The invention relates to a process for manufacturing a part having very high mechanical properties from a hot-rolled or cold-rolled steel strip, comprising precoating said strip with aluminum or an aluminum alloy, cold deformation of the coated strip, possible cutting of the excess sheet with a view to the final geometry of the part, heating of the part so as to form an intermetallic compound from the steel/precoat interface and to austenitize the steel, transfer of the part to a tool and cooling of the part in the tool at a rate such that the steel has, after being cooled, a martensitic or bainitic structure or a martensite-bainite structure. The precoating is carried out by electroplating, by chemical or physical vapor deposition or by co-rolling.

Abstract: Hot-rolled steel with very high elasticity limit and mechanical resistance usable in particular for auto parts production, characterized by the following composition by weight: 0.08%<carbon<0.16% 1%<manganese<2% 0.02%<aluminum<0.1% silicon<0.5% phosphorus<0.03% sulfur<0.01% vanadium<0.3% chromium<1% nitrogen<0.015% molybdenum<0.6%.

Abstract: Hot-rolled steel with very high elasticity limit and mechanical resistance usable in particular for auto parts production, characterized by the following composition by weight:

Abstract: Hot-rolled steel sheet which then can be cold-rolled, coated, the steel in the sheet having the following composition by weight: 0.15%<carbon<0.5% 0.5%<manganese<3% 0.1%<silicon<0.5% 0.01%<chromium<1% titanium<0.2% aluminum<0.1% phosphorus<0.1% sulfur<0.05% 0.0005%<boron<0.08%, the remainder being iron and impurities inherent in processing, the sheet ensuring a very high mechanical resistance after thermal treatment and the aluminum-based coating ensuring a high resistance to corrosion.

Abstract: Hot-rolled steel sheet which then can be cold-rolled, coated, the steel in the sheet having the following composition by weight: 0.15%<carbon<0.5% 0.5%<manganese<3% 0.1%<silicon<0.5% 0.01%<chromium<1% titanium<0.2% aluminum<0.1% phosphorus<0.1% sulfur<0.05% 0.0005%<boron<0.08%, the remainder being iron and impurities inherent in processing, the sheet ensuring a very high mechanical resistance after thermal treatment and the aluminum-based coating ensuring a high resistance to corrosion.

Abstract: Hot-rolled steel sheet which then can be cold-rolled, coated, the steel in the sheet having the following composition by weight: 0.15%<carbon<0.5% 0.5%<manganese<3% 0.1%<silicon<0.5% 0.01%<chromium<1% titanium<0.2% aluminum<0.1% phosphorus<0.1% sulfur<0.05% 0.0005%<boron<0.08%, the remainder being iron and impurities inherent in processing, the shoot ensuring a very high mechanical resistance after thermal treatment and the aluminum-based coating ensuring a high resistance to corrosion.