冷坩埚无玷污悬浮熔炼

作者研制了一种水冷紫铜坩埚,供熔炼过渡元素合金,稀土元素合金之用,这种坩埚具有特殊的结构,在采用高频感应加热时,可在熔料及坩埚壁上产生特殊取向的涡流,使熔化的金属液与紫铜坩埚脱离接触而悬浮在冷坩埚中,从而避免了坩埚对熔料所可能产生的污染。试验结果表明,熔料可达到的最高温度不低于2500K;坩埚的铜质对熔锭並无污染;熔锭成分均匀,配以保护气氛时,表向洁净。熔锭的典型体积为4.5cm~3。这种无玷污悬浮熔炼特别适用于精密合金材料的研制。作者曾用本法研究钕铁硼永磁,短期內即获得成功。

THE NON-CONTAMINATION SUSPENSION MELTING IN THE COLD CRUCIBLE

The authors developed a water-cooled cold crucible made of copper for the melting of transition-metal alloys and rare earth alloys. This crucible has a special structure which produces eddy currents in the melting alloy and in the wall of the crucible when they are induction heated. The molten alloy is thus suspended in the center of the crucible, and the possible contamination from the crucible is avoided. The results indicate that the maximum temperature of the molten alloys is not lower than 2500K, the copper of the crucible does not enter into the ingots of alloys, and the ingots are very homogeneous. The typical volume of ingots is about 4.5cm~3. The non-contamination suspension melting is very useful in the stndy of new alloy systems. The authors used this technique to study Nd-Fe-B permanent magnets and obtained good results