Abstract:
THIS IS A IMPROVEMENT IN A MOLTEN ALUMINUM REFINING PROCESS OF THE TYPE DESCRIBED IN U.S. PAT.3,039,864 WHERE A NON-REACTIVE FLUXING GAS IS PASSED THROUGH MOLTEN ALUMINUM AS IT MOVES THROUGH A BED OF REFRACTORY BODIES TO REMOVE FROM THE ALUMINUM HYDROGEN GAS AN NON-METALLIC IMPURITIES SUCH AS OXIDES. ACCORDING TO THE IMPROVEMENT A RELATIVELY SMALL STREAM OF A REACTIVE CHLORINACEOUS FLUXING GAS INTRODUCED ALONG WITH THE NON-REACTIVE FLUXING GAS SUBSTANTIALLY INCREASES THE USEFUL LIFE OF THE REFRACTORY BODY BED. THE PROCESS IS CAPABLE OF CHLORINE FUME-FREE OPERATION.
Abstract:
Use of particles of aluminum having an oxide coating obtained by active oxidation thereof to prevent sticking together of aluminum powder metallurgy parts stacked or piled during sintering.
Abstract:
THE SODIUM OXIDE AND HYDROGEN CONTENT OF MOLTEN ALUMINUM IS DRASTICALLY REDUCED BY MOVNG THE MOLTEN ALUMINUM THROUGH TWO PURIFYING ZONES. IN EACH ZONE THE MOLTEN ALUMINUM IS MOVED THROUGH A BED OF REFRACTORY BODIES IN CONTACT WITH FLUXING GASES. CONDITIONS ARE CAREFULLY MAINTAINED TO REMOVE IMPURITIES WHILE PREVENTING DETERIORATION OF THE BEDS. THE PROCESS CAN BE OPERATED ON A POLLUTION FREE BASIS AND YET ACHIEVE EXTREMELY LOW IMPURITY LEVELS.
Abstract:
THE SODIUM CONTENT OF MOLTEN ALUMINUM ALONG WITH THE OXIDE AND HYDROGEN GAS CONTENT, IS REDUCED BY AN IMPROVED PROCESS WHEREIN THE MOLTEN ALUMINUM IS PASSED THROUGH A BED OF REFRACTORY BODIES. THE REFRACTORY BODIES HAVE THEIR SURFACES ACTIVATED BY CHLORINE AND ARE REACTIVE TO THE SODIUM IMPURITIES. THE REFRACTORY BODY BED IS CONTINUOUSLY FLUSHED WITH A NON-REACTIVE GAS FUX TO REMOVE CHLORINE REACTION PRODUCTS FORMED IN THE BED. THE IMPROVEMENT IS CAPABLE OF CHLORINE FUME-FREE OPERATION AND ACCORDINGLY IS ESPECIALLY USEFUL WHERE POLLUTION CONTROL IS IMPORTANT.