The invention relates to a device (10) and to a method for producing a continuous strip-shaped composite material (11). A base material of metal, which is unwound in the form of a metal strip (13) by a first coil-unwinding apparatus (12), and at least one cladding material of metal, which is unwound in the form of a metal strip (15) by a second coil-unwinding apparatus (14), are provided. Then, the metal strips (13, 15) unwound by said coil-unwinding apparatuses (12, 14) are brought together in the hot state, wherein then the unwound metal strips (13, 15) brought toward each other are hot-rolled such that a single continuous strip-shaped composite material (11) is thus formed by roll cladding, said composite material consisting of the base material and the cladding material. Both the base material and the cladding material and the metal strips (13, 15) thereby unwound each consist of steel.

Provided is a continuous casting method of steel that prevents a solidification completion position from being changed even when a drawing speed V of a cast slab is changed. The method includes drawing a cast slab by setting a drawing speed V0 while spraying cooling water to the cast slab at a cooling water spray amount W0 [kg/ton-cast slab]. Then, changing the drawing speed to the speed V1 while spraying cooling water to the cast slab at a cooling water spray amount W1 [kg/ton-cast slab]. The method further includes spraying cooling water to the cast slab at a cooling water spray amount Wt [kg/ton-cast slab] during a period of time t that is obtained by dividing a target length Lt by the drawing speed V0. The water spray amount Wt satisfying either formula (1): Wt<W1 under a condition of V1<V0, or formula (2): Wt>W1 under a condition of V1>V0.

A method and a device for producing a continuous strip-shaped composite material. The device has at least one first casting machine, using which a continuous strand is produced, in particular from steel, at least one rolling stand, which is arranged in line with the first casting machine and downstream thereof. A fully solidified slab of the strand produced using the first casting machine can be hot rolled, and at least one second casting machine, using which a further continuous strand is produced from metal. Between the casting machines, on the one hand, and the rolling stand, on the other hand, a merging unit is arranged, by means of which the slabs can be moved in the direction toward each other in the hot state. The rolling stand is designed as a roll-cladding unit, by which a composite formed from the merged slabs can be hot rolled.

The invention concerns a method and a plant for obtaining strips (S), wherein the plant has at least three casting lines (11, 12, 13) disposed in parallel, of which two are lateral (11, 13) and one is central (12), and at least two rolling lines (14, 15) aligned with two of said at least three lateral casting lines (11, 12 13).

A steel plant for the production of long metal products includes a continuous casting machine and a rolling mill disposed contiguous and in direct succession downstream of the continuous casting machine. The continuous casting machine is provided with at least two casting lines and the rolling mill is provided with at least two rolling lines. The plant includes a single feed apparatus for feeding molten metal, and the at least two casting lines are configured to receive molten metal from the single feed apparatus.

An apparatus (100) and method for the production of elongated metal products such as bars, rods or the like: A rolling mill (10) with at least one rolling stand (5); a casting station (20) with at least a first casting line (2a) and at least a second casting line (2b), each line (2a, 2b) being operable to produce respective elongated intermediate products (b2a, b2b), such as billets; wherein at least the first casting line (2a) is directly aligned with the rolling mill (10), the first casting line (2a) being configured to feed the rolling mill (10) with a fully continuous casting strand or with cast elongated intermediate products; and the second casting line (2b) is not aligned with the rolling mill (10). A bidirectional transfer device (30) for transferring elongated intermediate products (b2b) of the second casting line (2b) alternatively in a first direction from the second casting line (2b) to the first casting line (2a) to align the elongated intermediate product (b2b) with the rolling mill (10) or in a second direction from the at least second casting line (2b) to a cooling bed (40).

A dual hardness steel article comprises a first air hardenable steel alloy having a first hardness metallurgically bonded to a second air hardenable steel alloy having a second hardness. A method of manufacturing a dual hard steel article comprises providing a first air hardenable steel alloy part comprising a first mating surface and having a first part hardness, and providing a second air hardenable steel alloy part comprising a second mating surface and having a second part hardness. The first air hardenable steel alloy part is metallurgically secured to the second air hardenable steel alloy part to form a metallurgically secured assembly, and the metallurgically secured assembly is hot rolled to provide a metallurgical bond between the first mating surface and the second mating surface.

Method for the production of flat metal products, in particular coils of strip, in endless and/or semi-endless mode, in which a metal product is continuously fed to a rolling mill consisting overall of at least 4 stands. The rolling stands are, in sequence, roughing stands, and finishing stands. It is provided to perform a flying gauge change of the metal product exiting from the rolling mill.

A dual hardness steel article comprises a first air hardenable steel alloy having a first hardness metallurgically bonded to a second air hardenable steel alloy having a second hardness. A method of manufacturing a dual hard steel article comprises providing a first air hardenable steel alloy part comprising a first mating surface and having a first part hardness, and providing a second air hardenable steel alloy part comprising a second mating surface and having a second part hardness. The first air hardenable steel alloy part is metallurgically secured to the second air hardenable steel alloy part to form a metallurgically secured assembly, and the metallurgically secured assembly is hot rolled to provide a metallurgical bond between the first mating surface and the second mating surface.

A non-scaling heat-treatable steel with particular suitability for producing hardened or die-hardened components is disclosed, characterized by the following chemical composition in % by weight: C 0.04-0.50; Mn 0.5-6.0; Al 0.5-3.0; Si 0.05-3.0; Cr 0.05-3.0; Ni less than 3.0; Cu less than 3.0; Ti 0.0104-0.050; B 0.0015-40.0040; P less than 0.10; S less than 0.05; N less than 0.020; remainder iron and unavoidable impurities. Further disclosed is a method for producing a non-scaling hardened component from the steel and a method for producing a hot strip from a steel.