Abstract: A method of controlling heat flux between the casting pool and the surfaces of the casting roll in a strip steel casting process includes controlling the concentration of nitrogen in the steel melt. The concentration of nitrogen may be controlled to achieve an operational heat transfer to the casting roll. The beat flux to the casting rolls may be controlled by maintaining the sum of partial pressures calculated from the nitrogen and hydrogen concentrations in the casting pool below 1.15 atmospheres. Decreasing the concentration of nitrogen can increase heat flux at the casting rolls.

Abstract: A thin cast steel strip and method of making thereof with improved resistance to microcracking, where the steel strip is produced by continuous casting and contains between about 0.003% and about 0.008% sulfur by weight and about 0.010% and about 0.065% carbon by weight. The sulfur content may be between about 0.003% and 0.006%.

Abstract: A method of controlling heat flux between the casting pool and the surfaces of the casting roll in a strip steel casting process includes controlling the concentration of nitrogen in the steel melt. The concentration of nitrogen may be controlled to achieve an operational heat transfer to the casting roll. The beat flux to the casting rolls may be controlled by maintaining the sum of partial pressures calculated from the nitrogen and hydrogen concentrations in the casting pool below 1.15 atmospheres. Decreasing the concentration of nitrogen can increase heat flux at the casting rolls.

Abstract: A method of casting steel strip by introducing molten plain carbon steel on casting surfaces at least one casting roll with the molten steel having a free nitrogen content below 120 ppm and a free hydrogen content below about 6.9 ppm. The free nitrogen content maybe below about 100 ppm or below about 85 ppm. The free hydrogen content maybe between 1.0 and 6.5 ppm at atmospheric pressure. Novel cast strip of plain carbon steel is produced having a strip thickness less than 5 mm or less than 2 mm by use of the method.

Abstract: A method for making a thin cast strip with reduced meniscus marks includes assembling a pair of casting rolls laterally positioned to form a nip therebetween, preparing molten steel having a carbon content in the range of 0.01 to 0.3% by weight, a manganese content between 0.1 and 0.8% by weight, a silicon content between 0.05 and 0.5% by weight, a calcium content between 0.0008 and 0.004% by weight, an aluminum content between 2 and 500 ppm by weight, having a free oxygen content below about 50 ppm at 1600 ° C., forming a casting pool of the molten steel supported on casting surfaces of the casting rolls above the nip, and counter-rotating the casting rolls cause thin strip to be casted downwardly from the nip.

Abstract: A refractory material for steelmaking is comprised of 50 to 95% zirconia (ZrO2), 0 to 35% of silica (SiO2), 5 to 35% carbon (C), less than 5% alumina (Al2O3) and anti-oxidant such as silicon (Si) metal and a carbide. The anti-oxidant may be in amounts up to about 10% by weight. The refractory material has application in making delivery nozzles and transition pieces. Disclosed also is a method of continuous casting steel strip comprising the steps of assembling a pair of casting rolls having a nip between them; assembling a delivery system for delivering molten steel to form a casting pool comprised of at least some refractory material for contacting the molten steel comprised of 50 to 95% zirconia, 0 to 35% silica, 5 to 35% carbon, less than 5% alumina and anti-oxidant and carbides, and rotating the casting rolls to form thin steel strip delivered downwardly through the nip.

Abstract: A method of casting steel strip by introducing molten plain carbon steel on casting surfaces at least one casting roll with the molten steel having a free nitrogen content below 120 ppm and a free hydrogen content below about 6.5 ppm measured at atmospheric pressure. The free nitrogen content maybe below about 100 ppm or below about 85 ppm. The free hydrogen content maybe between 1.0 and 6.5 ppm at atmospheric pressure. Novel cast strip of plain carbon steel is produced having a strip thickness less than 5 mm or less than 2 mm by use of the method.