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.

An austenitic stainless steel having excellent processability and surface characteristics and a method of manufacturing the austenitic stainless steel are disclosed. The austenitic stainless steel includes, by weight %, 0.005% to 0.15% of carbon (C), 0.1% to 1.0% of silicon (Si), 0.1% to 2.0% of manganese (Mn), 6.0% to 10.5% of nickel (Ni), 16% to 20% of chromium (Cr), 0.005% to 0.2% of nitrogen (N), the remainder iron (Fe) and other unavoidable impurities, wherein a degree of Ni surface negative segregation defined by the following Formula (1) is in a range of 0.6 to 0.9.
(C.sub.Ni-Min)/(C.sub.Ni-Ave)  Formula (1), where C.sub.Ni-Min is a minimum concentration of Ni on the surface of the austenitic stainless steel and C.sub.Ni-Ave is an average concentration of Ni on the surface of the austenitic stainless steel.

A roller stand for a continuous billet casting machine, having a carrying frame for mounting at least one lower supporting roller and at least two lateral supporting rollers. The lateral supporting rollers are mounted elastically on the carrying frame by means of at least one passive elastic element, and have an amount of elasticity at least in a direction perpendicular to the axes of rotation of the lateral supporting rollers. A method for determining the position and/or the shape of a billet is provided. During passage through at least one roller stand, alterations in the position at least of the lateral supporting rollers relative to a reference are detected and, on the basis of this information, the shape of the billet and/or the position of the billet in relation to the center line of the billet-guide channel are/is determined.

A non-oriented electrical steel sheet according to one embodiment of the invention has a chemical composition represented by C: 0.0030% or less, Si: 2.00% or less, Al: 1.00% or less, Mn: 0.10% to 2.00%, S: 0.0030% or less, one or more selected from the group consisting of Mg, Ca, Sr, Ba, Nd, Pr, La, Ce, Zn, and Cd: greater than 0.0100% and not greater than 0.0250% in total, a parameter Q represented by Q=[Si]+2×[Al]−[Mn]: 2.00 or less; Sn: 0.00% to 0.40%, Cu: 0.00% to 1.00%, and a remainder: Fe and impurities, and a parameter R represented by R=(I.sub.100+I.sub.310+I.sub.411+I.sub.521)/(I.sub.111+I.sub.211+I.sub.332+I.sub.221) is 0.80 or greater.

An in-mold solidified shell thickness estimation apparatus includes: an input device; a model database configured to store a model formula and a parameter related to a solidification reaction of a molten steel inside a mold of a continuous casting facility; and a heat transfer model calculator configured to estimate an in-mold solidified shell thickness by calculating temperature distributions of the mold and of the molten steel inside the mold by solving a three-dimensional unsteady heat transfer equation. The heat transfer model calculator is configured to correct errors in a temperature of a mold copper plate and in an amount of heat removed from the mold, by correcting an overall heat transfer coefficient between the mold copper plate and the solidified shell.

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.

Secondary cooling apparatus in a machine for continuous casting of metal products, such that each metal product is cast, contained and guided along an axis of movement. The secondary cooling apparatus includes a plurality of cooling assemblies disposed in sequence one to the other along the continuous casting machine. Each assembly includes a plurality of cooling units each provided with one or more nozzles disposed along the axis of movement. The cooling units of each assembly are adjacent to each other to cover a width at least equal to the maximum width of the metal product which can be cast in the continuous casting machine.

Method to control a secondary cooling apparatus in a machine for continuous casting of metal products. The secondary cooling apparatus includes a plurality of cooling units equipped with nozzles, each nozzle is provided with delivery orifices from which a refrigerant fluid is delivered, on each occasion according to the punctual cooling needs, toward a metal product.

A method of manufacturing a round steel billet by continuous casting includes a local cooling step where inhomogeneous forced cooling is applied to a cast product during the continuous casting, and a rolling reduction step where rolling reduction is applied to the cast product in the opposite directions of the polar opposites by reduction rolls in the course from the completion of solidification to the completion of the recuperation of the cast product so that rolling reduction r which is a reduction ratio of a distance between middle points of the polar opposites is set to a value exceeding 0% and 5% or less.

To achieve a substantially uniform microstructure across a continuously cast thin metal strip, it is beneficial to cool a width of the strip to a substantially constant temperature before further cooling the strip to reach any desired phase transformation temperature. Accordingly, methods of continuously casting a thin metal strip may include moving the thin strip to a cooling section, the cooling section having a plurality of coolant discharge ports configured to discharge a flow of coolant along the thin strip; initially sensing the temperature of the thin strip to determine a temperature distribution across the width of the thin strip, and producing a sensor signal corresponding to a sensed temperature at each of the first plurality of locations; and individually controlling the cooling across a width of the thin strip by way of the plurality coolant discharge ports in each zone of a first row using the determined temperature distribution.