【7/12更新】2022年4月1日からのCiNii ArticlesのCiNii Researchへの統合について

<報文>炭素溶融還元-電子ビーム溶解法による高純度ニオブの精製錬

書誌事項

タイトル別名
  • <Original Papers>Production of Pure Niobium by Combination of Carbon Reduction Smelting and Electron Beam Melting

この論文をさがす

抄録

type:紀要類(bulletin)

The interest in high-purity niobium has risen from the need for materials in the high temperature, superconductivity and atomic energy fields recently. In this work, the combination method, i.e. carbon reduction smelting of niobium oxide at about 2900K in Ar plasma arc and refining of the reduced-niobium with electron beam melting, was carried out to prepare high-purity massive niobium metal. The results obtained are summerized as follows : (1) Each pellet of mixture with a ratio of graphite to niobium pentoxide, C/Nb_2O_5,was selected 4.8,4.9,5.0 and 5.1,was pre-reduced prior to the reduction smelting. In Ar plasma arc heating, reduction proceeded rapidly with melting down of each pellet and the elimination of carbon and oxygen as CO-degassing proceeded slowly in the Nb-C-O molten state. Niobium of above 99% purity was obtained by a 12 min treatment. (2) Carbon and oxygen content in the reduced-niobium was dependent on the C/Nb_2O_5 ratio and in the relation between carbon and oxygen it was found that (%C)×(%O) was almost constant. It is, therefore, able to adjust carbon/oxygen ratio in the reduced-niobium by changing C/Nb_2O_5 ratio for next refining process. (3) At electron beam melting, remarkable deoxidation was found by evaporation of NbO and/or NbO_2,but decarburization as CO-degassing was possible only when excess oxygen was present in the reduced-niobium. (4) Ductile high-purity niobium, the carbon and oxygen content were 20ppm, 70ppm respectively, with a hardness of 50 HMV was produced by electron beam melting of the reduced-niobium at C/Nb_2O_5=4.9. (5) Evaporation loss of niobium besides niobium suboxide during electron beam melting decreased the recovery of niobium. (6) Metal impurities, such as Fe, Al, Si, which are more volatile than niobium were removed effectively to the levels of a few ppm with electron beam melting.

Niobium

Carbon Reduction

Reduction

Smelting

Plasma Arc

Electron Beam Melting

Deoxidation

Decarburization

Purification

Refining

収録刊行物

被引用文献 (0)

もっと見る

参考文献 (0)

もっと見る

関連論文

もっと見る

関連研究データ

もっと見る

関連図書・雑誌

もっと見る

関連博士論文

もっと見る

関連プロジェクト

もっと見る

関連その他成果物

もっと見る

詳細情報

ページトップへ