The invention relates to a method and to a spraying apparatus (10) for the thermal surface treatment of a metal product (1). The metal product (1) is conveyed in a transport direction (T) through a treatment section (12) of a spraying apparatus (10) equipped with cooling nozzles (16) while cooling fluid is discharged through the cooling nozzles (16) of the spraying apparatus (10) onto the surfaces of the metal product (1), wherein the metal product (1) has—viewed in the transport direction (T) of the metal product (1)—a front section (4) and a trailing rear section (5). The cooling of the surfaces of the metal product (1) within the spraying apparatus (10) occurs in such a manner that the rear section (5) of the metal product (1) is cooled more significantly than its front section (4). It is thereby achieved that an essentially uniform ferrite content forms in the material of the metal product (1) at a predetermined depth of the same over a longitudinal area extending between the front section (4) and the rear section (5).

An electromagnetic stirring device and a method for a secondary cooling zone during slab continuous casting. The device has a main body, an opening adjustment assembly, and a secondary cooling assembly. The main body has a protection housing (3), a phase sequence control assembly, an iron core (4) and an electromagnetic coil (5) for carrying out variable-direction electromagnetic stirring on a molten steel by a three-phase current phase sequence transformation. The opening adjustment assembly has an air cylinder (7), a fixed base (8), a movable joint shaft (12) and a silicon steel sheet group insert (13) for adjusting online opening degree of the closed annular iron core by a movable joint structure. The secondary cooling assembly has a cooling water inlet (9) and a cooling water nozzle (10) for cooling the electromagnetic coil and spraying cooling water to a surface of a cast slab (1).

A plant to produce metal products, and a corresponding management method, where the plant includes a production line which includes a plurality of operating units, each provided with respective hydraulic circuits, selected from a melting unit, a casting unit, a rolling unit and a cooling treatment apparatus, and a water supply unit having a tank for the water connected to each of the hydraulic circuits and a plurality of water feed devices configured to feed water from the tank to respective hydraulic circuits.

A secondary cooling control method for reinforcing surface solidification structure of microalloyed steel continuous casting bloom includes: in situ observing precipitation behavior of secondary phase particles of the microalloyed steel, and determining a concentrated precipitation temperature range; cooling the microalloyed steel at different cooling rates, obtaining a particle size and a volume fraction of the secondary phase particles of the microalloyed steel at different cooling rates; determining an optimal average cooling rate; determining an optimal average cooling rate r; determining an optimal average cooling rate; and determining an optimal average cooling rate range through intersection of the three optimal average cooling rates whereby the continuous casting secondary cooling is optimized. The present invention can enhance the surface solidification structure of continuous casting bloom and reduce surface and subsurface cracks of the microalloyed steel continuous casting bloom.

Provided are a steel sheet having a predetermined chemical composition and having the following steel structure, and a method of manufacturing the steel sheet.

(1) In area ratio %, ferrite: 0 to 5%, martensite: 90 to 100%, a ratio of tempered martensite to total martensite: 80 to 100%, and retained austenite: 0.5 to 6.0% are contained.

(2) The number density of inclusions satisfying the maximum diameter≥3 μm is 40 inclusions/mm.sup.2 or less.

(3) When the number density of the inclusions satisfying the maximum diameter≥3 μm in each section is calculated, the number density in the section where the number density of inclusions is in the top 10% is 80 inclusions/mm.sup.2 or less.

(4) Formula (A) is satisfied.

Vγ′/Vγ≥0.1  (A)

Vγ: Initial retained austenite, Vγ′: Retained austenite after deep cooling at −196° C.

(5) The tensile strength is 1470 MPa or more.

The present invention provides a method for producing a Cu—Ni—Sn alloy, which achieves both productivity and product quality by reducing internal cracks and dispersing Sn uniformly while shortening the time for cooling an ingot. The method for producing a Cu—Ni—Sn alloy is a method for producing a Cu—Ni—Sn alloy by a continuous casting method or a semi-continuous casting method, the method including: pouring a molten Cu—Ni—Sn alloy from one end of a mold, both ends of which are open, and continuously drawing out the alloy as an ingot from the other end of the mold while solidifying a part of the alloy, the part being near the mold; performing primary cooling by spraying a liquid mist on the drawn-out ingot; and performing secondary cooling by immersing the ingot having been subjected to the primary cooling in a liquid, thereby making a cast product of the Cu—Ni—Sn alloy.

A process for manufacturing an aluminum-based alloy sheet directly from a molten aluminum-based alloy is described. In a continuous caster, such as a belt-caster, and directly from the molten aluminum-based alloy, a substantially solid and substantially thin aluminum-based alloy strip, thinner than about 10 mm, is continuously cast and simultaneously cooled with a compression force on the solidifying aluminum-based alloy in a range of about 2 to about 3000 pounds per linear inch of alloy strip width. The substantially solid aluminum-based alloy strip can then be rolled, so as to obtain the aluminum-based alloy sheet. The process can include pulse heating the aluminum-based allowed sheet.

There is provided a method for producing a Cu—Ni—Sn alloy by a continuous casting method or a semi-continuous casting method, the method including pouring a molten Cu—Ni—Sn alloy from one end of a mold, both ends of which are open, and continuously drawing out the alloy as an ingot from the other end of the mold while solidifying a part of the alloy, the part being near the mold; and spraying mist-like liquid on the drawn-out ingot to cool the ingot, thereby making a cast product of the Cu—Ni—Sn alloy.

A method for improving center segregation and surface crack of continuous casting medium-thick slab of peritectic steel reduces the cooling intensity at the earlier stage of solidification and enhancing the cooling intensity at the final stage of solidification. For example, the cooling water amount of the wide face of the mould is 3400-3600 L/min, and the cooling water amount of the narrow face of the mould is 480-530 L/min. The cooling water amount of the wide face of the foot roller section is 239-298 L/min, and the cooling water amount of the narrow face of the foot roller section is 61-65 L/min. The total cooling water amount of the sector segment is 1517-2166 L/min.

A coolant nozzle (1) for cooling a metal strand in a continuous casting installation has a mouthpiece (5), which is arranged at a nozzle outlet end (4) and through which liquid coolant (6) can emerge from the coolant nozzle (1). To allow a rapid buildup of pressure at the coolant nozzle (1), it provides a feed (8), which is formed as a tube-in-tube system (9) arranged upstream of the mouthpiece (5) in the direction of through-flow (7) and has a feed outlet end (10), through the first tube (11) in which control air (13) can be brought up to the feed outlet end (10) and through the second tube (12) of which the liquid coolant (6) can be fed to the mouthpiece (5) by way of the feed outlet end (10), and also provides a control valve (14), which is integrated in the feed (8), is arranged at the feed outlet end (10), can be actuated pneumatically by using the control air (13) and is intended for controlling the feed of the liquid coolant (6) into the mouthpiece (5).