There is provided a cast strip manufacturing method including: supplying a molten steel stored in a tundish (18) to a molten steel pool portion (16) formed by a pair of rotating cooling rolls (11) and a pair of side dams via an immersion nozzle (20); and forming and growing a solidified shell on a circumferential surface of the cooling roll (11) to manufacture a cast strip (1), in which a Si additive is added to the molten steel in the tundish (18), a Si concentration of the molten steel is adjusted to be within a fixed range, and a temperature of the molten steel in the tundish (18) is controlled to be within a fixed range.

There is provided a cast strip manufacturing method including: supplying a molten steel stored in a tundish (18) to a molten steel pool portion (16) formed by a pair of rotating cooling rolls (11) and a pair of side dams via an immersion nozzle (20); and forming and growing a solidified shell on a circumferential surface of the cooling roll (11) to manufacture a cast strip (1), in which a Si additive is added to the molten steel in the tundish (18), a Si concentration of the molten steel is adjusted to be within a fixed range, and a temperature of the molten steel in the tundish (18) is controlled to be within a fixed range.

The present invention relates to steel sheet realizing both formability and weldability. The steel sheet of the present invention is characterized in that at a surface layer part of a region down to 30 μm from the surface of the steel sheet in the sheet thickness direction, Si oxide grains are present in 3000 to 6000/mm.sup.2 in number density, an average of natural logarithms of the particle sizes of the Si oxide grains measured in m units is −2.0 to −1.2, the standard error of the natural logarithms of the particle sizes is 0.6 or less, and the number of Si oxide grains with deviations of the natural logarithms of the particle sizes from the average larger than 2 times the standard error is 5% or less of the total number of Si oxide grains and at a position of ½ of the thickness of the steel sheet, the number density of the Si oxide grains is 1000/mm.sup.2 or less.

Provided is a mold flux used for casing a cast slab, the mold flux including, bases on a total wt % of thereof, 32-38 wt % of aluminum oxide (Al.sub.2O.sub.3), 8-12 wt % of strontium oxide (SrO), 8-12 wt % of potassium oxide (K.sub.2O), 8-12 wt % of fluorine (F), 5-8 wt % of boron oxide (B.sub.2O.sub.3), 3-5 wt % of lithium oxide (Li.sub.2O), and inevitable impurities. Thus, according to the mold flux, a change in components due to silicon oxide (SiO.sub.2) and calcium oxide (CaO) may be suppressed or prevented compared to those in the conventional art.

Provided is a mold flux used for casing a cast slab, the mold flux including, bases on a total wt % of thereof, 32-38 wt % of aluminum oxide (Al.sub.2O.sub.3), 8-12 wt % of strontium oxide (SrO), 8-12 wt % of potassium oxide (K.sub.2O), 8-12 wt % of fluorine (F), 5-8 wt % of boron oxide (B.sub.2O.sub.3), 3-5 wt % of lithium oxide (Li.sub.2O), and inevitable impurities. Thus, according to the mold flux, a change in components due to silicon oxide (SiO.sub.2) and calcium oxide (CaO) may be suppressed or prevented compared to those in the conventional art.

There is provided a cast strip manufacturing method including: supplying a molten steel stored in a tundish (18) to a molten steel pool portion (16) formed by a pair of rotating cooling rolls (11) and a pair of side dams via an immersion nozzle (20); and forming and growing a solidified shell on a circumferential surface of the cooling roll (11) to manufacture a cast strip (1), in which a Si additive is added to the molten steel in the tundish (18), a Si concentration of the molten steel is adjusted to be within a fixed range, and a temperature of the molten steel in the tundish (18) is controlled to be within a fixed range.

There is provided a cast strip manufacturing method including: supplying a molten steel stored in a tundish (18) to a molten steel pool portion (16) formed by a pair of rotating cooling rolls (11) and a pair of side dams via an immersion nozzle (20); and forming and growing a solidified shell on a circumferential surface of the cooling roll (11) to manufacture a cast strip (1), in which a Si additive is added to the molten steel in the tundish (18), a Si concentration of the molten steel is adjusted to be within a fixed range, and a temperature of the molten steel in the tundish (18) is controlled to be within a fixed range.

A product comprising recycled metal fragments and an alloying supplement, and methods and system for producing same. In some examples, the product comprises a container, shot blasted pieces of aluminum alloy wheels and an alloying supplement. In some examples, the product also comprises an indication on the container of a composition estimate of the combined shot blasted pieces and alloying supplement. In other examples, the indication and/or the alloying supplement may be provided by a company in the business of providing alloying supplements.

A product comprising recycled metal fragments and an alloying supplement, and methods and system for producing same. In some examples, the product comprises a container, shot blasted pieces of aluminum alloy wheels and an alloying supplement. In some examples, the product also comprises an indication on the container of a composition estimate of the combined shot blasted pieces and alloying supplement. In other examples, the indication and/or the alloying supplement may be provided by a company in the business of providing alloying supplements.

Crystallizer for the continuous high-speed casting of a metal product (P), which has a casting cavity (13) defined by walls (14) connected to each other in correspondence with edges (15) and provided with cooling means (16).