Scholarlink

<p>Titanium aluminide alloys (TiAl alloys) are lightweight heat-resistant materials with excellent high-temperature tensile strength and creep strength-to-weight ratio. The development of a casting technique capable of producing high-quality ingots at low cost is expected to contribute to the wider application of TiAl alloys. Therefore, the objective of this study is to develop a CCIM casting process capable of producing Ti-48at.%Al-2at.%Cr-2at.%Nb (Ti-33.3wt.%Al-2.55wt.%Cr-4.8wt.%Nb) ingots with superior surface quality. After melting the raw materials in CCIM, the molten alloy was cast by bottom pouring to produce ingots with a diameter of φ60 mm and a height of over 1000 mm. Among the 81 ingots produced, 68 had good surfaces and 13 had irregular surfaces. During pouring, the center position of the pouring stream oscillated within a range of approximately 2.0–10.0 mm. However, it was clarified that oscillation of the pouring stream does not necessarily lead to surface irregularities. Surface irregularities occurred within the casting speed range of 0.05–0.12 kg/s, whereas no irregular surfaces were observed in the rang of 0.13–0.1 kg/s. Within the conditions of this study, it was clarified that increasing the casting speed is effective in suppressing surface irregularities. A larger graphite nozzle diameter resulted in a higher casting speed. Therefore, using a graphite nozzle with a larger diameter was found to be effective as a casting condition for suppressing surface irregularities.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Development of Practical Technique for Improving Surface Quality of Ti-48at.%Al-2at.%Nb-2at.%Cr Alloy Ingots Produced by Cold Crucible Induction Melting

  • 期刊论文

  • 发表日期：

    2026年3月17日

查看全文
  • Tomohiro Nishimura,
  • Shourin O

摘要

Titanium aluminide alloys (TiAl alloys) are lightweight heat-resistant materials with excellent high-temperature tensile strength and creep strength-to-weight ratio. The development of a casting technique capable of producing high-quality ingots at low cost is expected to contribute to the wider application of TiAl alloys. Therefore, the objective of this study is to develop a CCIM casting process capable of producing Ti-48at.%Al-2at.%Cr-2at.%Nb (Ti-33.3wt.%Al-2.55wt.%Cr-4.8wt.%Nb) ingots with superior surface quality. After melting the raw materials in CCIM, the molten alloy was cast by bottom pouring to produce ingots with a diameter of φ60 mm and a height of over 1000 mm. Among the 81 ingots produced, 68 had good surfaces and 13 had irregular surfaces. During pouring, the center position of the pouring stream oscillated within a range of approximately 2.0–10.0 mm. However, it was clarified that oscillation of the pouring stream does not necessarily lead to surface irregularities. Surface irregularities occurred within the casting speed range of 0.05–0.12 kg/s, whereas no irregular surfaces were observed in the rang of 0.13–0.1 kg/s. Within the conditions of this study, it was clarified that increasing the casting speed is effective in suppressing surface irregularities. A larger graphite nozzle diameter resulted in a higher casting speed. Therefore, using a graphite nozzle with a larger diameter was found to be effective as a casting condition for suppressing surface irregularities.