Abstract: The invention relates to the protection of a casting jet of molten metal, flowing between an upper storage tank and a lower receiving vessel. At least one inert liquefied gas is injected above and close to the surface of the molten metal contained in the lower vessel, and, at the same time, at least one inert gas is injected into the molten metal through the base or the walls of the lower vessel. The process of this invention protects metal casting jets from oxidation, for example, jets between ladle and manifold, between ladle and ingot mold, between ladle and ladle, or between converter (or furnace) and ladle.

Abstract: This invention relates to a method of casting metal in a rotary mould or die under the protection of an inertizing atmosphere formed by a liquefied gas. In the mould or die, successive casting operations are performed with different metals while maintaining an infeed of liquefied gas during each of these casting operations and while the metal involved is solidifying, until an end product is obtained which is formed from a plurality of layers of different metals. The invention is applicable in particular, but not exclusively, to the production of centrifugally cast tubes and rolling-mill rolls.

Abstract: The cooling of molten metal, such as metal continuously cast into an ingot mold, is retarded by establishing on the upper surface of the metal in the mold, a layer of cryogenic liquid such as nitrogen, helium or argon, with a finely divided material in homogeneous and stable suspension in the liquid. The finely divided material is in the form of particles having a size between 200 and 2,000 A and is present in a quantity between 10 and 1,000 grams per liter of cryogenic liquid. The suspended material may be aluminum, titanium, zirconium, niobium, calcium, lithium, magnesium, solid glass, or an oxide of aluminum, titanium, zirconium, niobium, calcium, lithium or magnesium, and is highly reflective to infrared radiation from the metal so as to reduce the transparency of the cryogenic liquid to this infrared radiation.

Abstract: A surface of molten metal is covered with a polyphase mixture of a cryogenic fluid and at least one additional constituent in the form of particles, the particles having a size less than 50 microns and forming a homogeneous and stable suspension in the boiling liquefied gas. The particles may be metal or metal oxide or glass or carbon or vegetable or mineral oil, and serve to reduce radiative heat losses from the metal by reflection and/or to serve as a lubricant of the metal in a mold.