The refining effect of Ar/Ar-H2 plasma arc melting (PAM) was investigated and the purity of Ta metals was evaluated by glow discharge mass spectrometry (GDMS). Most impurities in the Ta metals were removed by Ar/Ar-H2 PAM, down to a few mass ppm levels, and the purities of respective Ta metals refined by Ar/ Ar-20 % PAM were improved up to 5N5 (99.9995 %) and 5N7 (99.99972 %). It was also found that the deoxidation reaction under hydrogen plasma condition is enhanced by a remarkable decrease in the oxygen concentration of the Ta metal refined by Ar-H2 PAM.
|ジャーナル||Metals and Materials International|
|出版ステータス||Published - 2008 8月|
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