Abstract: The invention deals with a process for manufacturing a hot-dip galvanized or galvannealed steel sheet having a TRIP microstructure, said process comprising the steps consisting in: -providing a steel sheet whose composition comprises, by weight: 0.01?C?0.22%, 0.50?Mn?2.0%, 0.2?Si?2.0%, 0.005?Al?2.0%, Mo<1.0%, Cr?1.0%, P<0.02%, Ti?0.20%, V?0.40%, Ni?1.0%, Nb?0.20%, the balance of the composition being iron and unavoidable impurities resulting from the smelting, -oxidizing said steel sheet in a direct flame furnace where the atmosphere comprises air and fuel with an air-to-fuel ratio between 0.80 and 0.95, so that a layer of iron oxide having a thickness from 0.05 to 0.2 ?m is formed on the surface of the steel sheet, and an internal oxide of Si and/or Mn and/or Al is formed, -reducing said oxidized steel sheet, at a reduction rate from 0.001 to 0.

Abstract: One subject of the invention is a process for manufacturing a metal strip having a metal coating for corrosion protection, comprising the steps consisting in: making the metal strip pass through a bath of molten metal, comprising 0.2 to 8% by weight of aluminum and magnesium in the following proportions: 0.1 to 8% by weight of magnesium for an aluminum content equal to or greater than 0.2% but less than 4% by weight or a content greater than 5% but less than or equal to 8% by weight of magnesium for an aluminum content equal to or greater than 4% but less than or equal to 8% by weight, and comprising up to 0.

Abstract: The subject of the invention is a process for manufacturing a metal strip having a metal coating for corrosion protection, comprising the steps consisting in: making the metal strip pass through a bath of molten metal; then wiping the coated metal strip by means of nozzles that spray a gas on each side of the strip, said gas having an oxidizing power lower than that of an atmosphere consisting of 4% oxygen by volume and 96% nitrogen by volume; and then making the strip pass through a confinement zone bounded: at the bottom, by the wiping line and the upper faces of the wiping nozzles, at the top, by the upper part of two confinement boxes placed on each side of the strip, just above the nozzles, and having a height of at least 10 cm in relation to the wiping line and on the sides, by the lateral parts of the confinement boxes, the atmosphere in the confinement zone having an oxidizing power lower than that of an atmosphere consisting of 4% oxygen by volume and 96% nitrogen by volume and higher than that

Abstract: The invention deals with a process for manufacturing a hot-dip galvanized or galvannealed steel sheet having a TRIP microstructure, said process comprising the steps consisting in:—providing a steel sheet whose composition comprises, by weight: 0.01?C?0.22%, 0.50?Mn?2.0%, 0.2?Si?2.0%, 0.005?Al?2.0%, Mo<1.0%, Cr?1.0%, P<0.02%, Ti?0.20%, V?0.40%, Ni?1.0%, Nb?0.20%, the balance of the composition being iron and unavoidable impurities resulting from the smelting,—oxidizing said steel sheet in a direct flame furnace where the atmosphere comprises air and fuel with an air-to-fuel ratio between 0.80 and 0.95, so that a layer of iron oxide having a thickness from 0.05 to 0.2 ?m is formed on the surface of the steel sheet, and an internal oxide of Si and/or Mn and/or Al is formed,—reducing said oxidized steel sheet, at a reduction rate from 0.001 to 0.

Abstract: The invention relates to a metallurgical reactor for the treatment under reduced pressure of a liquid metal (1) such as steel, contained in a ladle (2), of the type comprising a chamber (25), connected to a gas-suction plant (30) which can maintain a reduced pressure therein, and two tubular snorkels (26, 27), the upper ends of which emerge in orifices (35, 36) made in the bottom (28) of the chamber (25) and the lower ends of which may be immersed in said liquid metal (1) contained in said ladle (2), one (26) of said snorkels, called the "ascending snorkel", having means (29) for injecting a gas into its internal space for the purpose of creating a circulatory motion in the liquid metal (1) between the ladle (2) and the chamber (25) during said treatment, the reactor also comprising an enclosure (17) which is provided with means (20) for injecting a gas into its internal space, these means being suitable for creating a pressure greater than atmospheric pressure in the enclosure (17), and the ladle (2) being p