Patent ID: 8016911
Filing Date: 2011-09-13
Classification: B22D

Abstract:
1. A method for preventing a rapid oxidation or combustion of a molten magnesium or magnesium alloy, comprising using a gas composition as a protective gas for preventing an oxidation or combustion of a molten magnesium or magnesium alloy in a magnesium or magnesium alloy production process, wherein the gas composition contains a fluorine-containing organic compound and a carrier gas, the fluorine-containing organic compound is selected from the group consisting of a hydrofluorocarbon, a hydrofluoroether, and mixtures of at least two of the foregoing, the hydrofluorocarbon is selected from the group consisting of 1,1,3,3,3-pentafluoropropene, 1,2,3,3,3-pentafluoropropene, 1,1,2,3,3-pentafluoropropene, 2,3,3,3-tetrafluoropropene, 3,3,3-trifluoropropene, and mixtures of at least two of the foregoing, and the hydrofluoroether is selected from the group consisting of difluoromethyl fluoromethyl ether, bisdifluoromethyl ether, methyl pentafluoroethyl ether, 1,2,2,2-tetrafluoroethyl trifluoromethyl ether, 2,2,2-trifluoroethyl trifluoromethyl ether, difluoromethyl 1,2,2,2-tetrafluoroethyl ether, difluoromethyl 2,2,2-trifluoroethyl ether, 1-trifluoromethyl-2,2,2-trifluoroethyl methyl ether, 1-trifluoromethyl-1,2,2,2-tetrafluoroethyl methyl ether, 1,1,1,2,2,3,3-heptafluoro-3-methoxypropane, and mixtures of at least two of the foregoing.