Cost reduction of TiAl by alternative production and integration of TiAl scrap recycling - concepts and vacuum-metallurgical equipment

• Autorzy: Lochbichler C. , Friedrich B. , Jarczyk G. , Scholz H.
• Języki publikacji: EN

Abstrakty

EN

Due to high corrosion resistance and low density titanium alum in ides show a great potential as material for structural applications in the aerospace and automotive industry. However the high actual production costs for semi-finished products slow down a break through to mass production of TiAl. Current research projects at IME, Aachen funded by AIF "Otto von Guericke" and BMBF aim on cost reduced production methods of TiAl and on the minimisation of downgrading TiAl scrap. This article presents firstly the state of the art of TiAl production by vacuum arc (re)melting (V AR) or induction skull melting (ISM). A comparison of new process routes under special consideration of recycling issues will follow. Innovative processing and equipment concepts are shown by intelligent combination of well known vacuum melting and remelting processes such as vacuum induction melting, specialized using ceramic lining and deoxidisation with e.g. electro slag remelting (ESR). For each process step and accordingly equipment the metallurgical opportunities are pointed out and the way to make use of them within the process route is described. Requirements on input material and final metal quality addicted to the processing route and refining techniques with their adjustment in respect to TiAl are mentioned. Selected results of laboratory and pilot scale experiments done at IME in Aachen and equipment needs therefore are shown.

Słowa kluczowe

EN

gamma-TiAl; recycling; VIM; ISM; ESR; VAR

• Wydawca: Politechnika Gdańska
• Czasopismo: Advances in Materials Science
• Rocznik: 2008
• Tom: Vol. 8, nr 1(15)
• Strony: 67--74
• Opis fizyczny: Bibliogr. 7 poz., rys.

Twórcy

autor

Lochbichler C.

autor

Friedrich B.

autor

Jarczyk G.

autor

Scholz H.

• IME Process Metallurgy and Metal Recycling, RWTH Aachen University, Germany

Bibliografia

• 1. Güther V., Otto A., Kestler A., Clemens H.: Processing of Gamma-TiAl Based Ingots and Their Characterization, in: Gamma Titanium Aluminides 1999, (ed. W. Kim, D.M. Dimiduk and M.H. Loretto), March 1999, International Symposium on Gamma Titanium Aluminides, San Diego, ISBN 0-87339-451-8, pp. 225-230.
• 2. Breig P.G., Scott S.W.: Induction Skull Melting of Titanium Aluminides, Materials & Manufacturing Processes, 4(1), p 73-83 (1989).
• 3. Blum M., Franz H., Jarczyk G., Seserko P., Laudenberg H.J., Segtrop K, Busse P.: Mass Production of Gamma TiAl Automobile Valves on Prototype Scale, in: Ti 2003 Science and Technology, (ed. Wiley-VCH, Weinheim), March 2004, ISBN 3-527-30306-5, Vol. 5, pp. 3011-3018.
• 4. Stoephasius J.C., Friedrich B.: Production of g-TiAl Ingots by Aluminothermic Reduction of TiO2 and Refining by ESR, in: Proceedings of EMC 2005, (ed. GDMB), 2005, ISBN 3-935797-25-7, Vol. 4, pp. 1429-1444.
• 5. Stoephasius J.C.: Untersuchungen zur Raffination aluminothermisch hergestellter TiAl-Elektroden in einer Elektroschlackeumschmelzanlage, diploma thesis, 2002, RWTH Aachen.
• 6. Scholz H.: Sicherheitsanalyse - Schmelzen von Titan im Vakuum Induktion- und Druck Elektroschlacke-Ofen, annual BMBF report, 2005, undisclosed.
• 7. Lochbichler C., Stoephasius J.C., Friedrich B.: Alternative Method for the Production of TiAl-based Alloys under Special Consideration of Recycling Issues, Light Alloys Seminar 2006, Clausthal.