A method, articles and compositions are described for the direct addition of manganese metal to molten aluminum, which provide more rapid dissolution of the manganese in the aluminum than has been possible heretofore. The manganese is added to the molten aluminum in powder form (minus 14 mesh) in intimate admixture with a flux capable of forming a molten phase at the temperature of the molten aluminum to which the mixture is added. The flux, which is employed in an amount from about 3 to about 10 percent by weight of the total manganese-flux composition, contains chlorides other than those of manganese, fluorides and mixtures of such chlorides and fluorides; the preferred flux being 40 percent sodium chloride, 40 percent potassium chloride and 20 percent cryolite (Na.sub.3 AlF.sub.6).
Metals are alloyed into aluminum using a solid compact comprised of particles containing a high concentration of the metal to be added. The compacts are prepared by blending finely divided particles of the metal containing material with a salt fluxing agent, then compacting the mixture into a readily useable form such as a pellet. The resultant pellet provides rapid dissolution of the alloying constituent in the aluminum whether cold charged to the furnace or added to a molten bath over a wide range of bath temperatures.
Manganese is alloyed into aluminum using a solid compact prepared by blending finely divided particles comprising beta manganese with aluminum particles and then compacting the mixture into a readily useable form such as a briquette. The resultant briquette provides rapid dissolution of the beta manganese in the aluminum and improved manganese recoveries. The beta manganese may be prepared by heating manganese to 1305.degree.-1990.degree. F. followed by water quenching and crushing to obtain a product of controlled particle size having a reduced percentage of fines.
The present invention relates to a highly efficient aluminum covering flux and a process for its preparation. The said covering flux comprises potassium chloride, sodium chloride, lithium chloride, potassium fluoride and sodium hydrosulfate, wherein the composition of the mentioned covering flux is: potassium chloride, 20-65 parts by weight; sodium chloride, 20-65 parts by weight; lithium chloride, 1-20 parts by weight; potassium fluoride, 0.3-5 parts by weight, sodium hydrosulfate, 0.2-3 parts by weight. The said covering flux can effectively prevent the oxidization of aluminum in the process of smelting aluminum and can increase the yield of aluminum.
