Removal of oxygen from titanium melt using hydrogen plasma arc: Challenge to 300 ppm
| Project/Area Number |
18K18929
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| Research Category |
Grant-in-Aid for Challenging Research (Exploratory)
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| Allocation Type | Multi-year Fund |
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| Review Section |
Medium-sized Section 26:Materials engineering and related fields
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| Research Institution | Tohoku University |
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Principal Investigator |
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| Co-Investigator(Kenkyū-buntansha) |
上田 恭介 東北大学, 工学研究科, 准教授 (40507901)
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| Project Period (FY) |
2018-06-29 – 2020-03-31
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| Project Status |
Completed (Fiscal Year 2019)
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| Budget Amount *help |
¥6,240,000 (Direct Cost: ¥4,800,000、Indirect Cost: ¥1,440,000)
Fiscal Year 2019: ¥2,730,000 (Direct Cost: ¥2,100,000、Indirect Cost: ¥630,000)
Fiscal Year 2018: ¥3,510,000 (Direct Cost: ¥2,700,000、Indirect Cost: ¥810,000)
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| Keywords | チタン / プラズマ / 脱酸 / 溶解プロセス / 高純度化 / 低コスト化 / 水素 / 原子状水素 / 二段階法 / 熱力学 / 水蒸気 |
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| Outline of Final Research Achievements |
The oxygen removal process from titanium melt, which was considered difficult in the past, has been established. The process consists of hydrogen plasma arc melting (first-step melting) and argon plasma arc melting (second-step melting). Oxygen removal from 0.127 mass% (1270 mass ppm) to 0.034 mass% (340 mass ppm) was achieved in the titanium melt by optimizing in melting conditions such as hydrogen partial pressure, melting time, gas flow rate and plasma current. Thermodynamic consideration suggested that the dissolved hydrogen introduced into titanium melt in response to the high hydrogen potential of active atomic hydrogen in plasma functions as a deoxidizer in the second-step melting. An international patent application was filed based on the results of this research.
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| Academic Significance and Societal Importance of the Research Achievements |
学術的意義：これまで確立されていなかったチタン融体からの脱酸法として、水素プラズマアーク溶解を基礎としたプロセスを300 mass ppmまでの酸素除去という実証データおよび熱力学的考察とともに提案した。
社会的意義：還元プロセスはチタン部材製造コストの約1/3を占める。off gradeスポンジチタンやチタンスクラップなどの低廉原料の有効利用には、主要な不純物元素である酸素を除去するプロセス構築が必要であった。チタン融体から効率的に酸素除去するプロセスが構築されたことでチタン部材の低価格化に貢献するとともに、輸送機器や化学プラントへのチタンの適用を通して省エネルギーや地球温暖化抑制に貢献する。
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Report
(3 results)
Research Products
(13 results)
