PURPOSE:To produce clean casting, and to eliminate surface flaw of rolled sheets, bu removing nonmetallic inclusions, by a method wherein a flux having special composition containing silicate, Na2O, B2O3, Al2O3 and CaO, is added into molten silver and/or silver alloys. CONSTITUTION:A flux composed of 38-60wt% silicate, 10-30wt% Na2O, 3- 35wt% B2O3, 0-5wt% Al2O3 and 0-5wt% CaO, is added into molten silver and/or silver alloys, and is melted. Thereby, non metallic inclusions in the molten metal are absorbed in said flux. Then the molten metal positined on a lower layer is cast into a mold, without flux which is positioned on an upper layer and may be mixed, thereby, clean castings are obtained. Sheet-material without surface flaw may be produced by rolling said castings.
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