| 摘要 |
PCT No. PCT/AT89/00105 Sec. 371 Date May 8, 1991 Sec. 102(e) Date May 8, 1991 PCT Filed Nov. 20, 1989 PCT Pub. No. WO90/06196 PCT Pub. Date Jun. 14, 1990.A process for the centrifugal casting of copper, copper alloys, or other oxygen sensitive alloys, such as bronze, is effective for avoiding or reducing the formation of an oxide layer on the inner surface of the casting. The process essentially consists of applying powdered borax in a layer thickness of 0.5 mm to 4 mm onto the still liquid inner surface of the casting immediately after pouring the casting. The preferred thickness of the borax is 1 mm to 3 mm. Finely divided mixtures of metals which have an affinity for oxygen, such Mg, Li, Ce, and/or powders of graphite and/or fire clay and/or charcoal, can also be combined with the borax as additional additives for special casting processes. Apparatus for introducing the borax into the mold includes a trough which is extendable into the interior of the mold. The trough is either rotatably supported in a housing that is movable relative to the mold, or pivotally supported along a bottom portion of a pouring tube which is movable relative to the mold.
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