Development of alumina forming coatings for titanium aluminides.

• Autorzy: Singheiser L. , Niewolak L. , Shemet V. , Gil A. , Quadakkers W.J.

Warianty tytułu

EN

Rozwój pokryć z tlenkiem glinu do aluminidków tytanu.

• Konferencja: XVIth Physical Metallurgy and Materials Science Conference on Advanced Materials and Technologies AMT'2001, Gdańsk-Jurata, 16-20 September 2001
• Języki publikacji: PL

Abstrakty

EN

One important hindrance for the use of gamma-TiAl alloys at high temperatures is their relatively poor oxidation resistance and the sensitivity against environmentally induced embrittlement. The latter effect is also of major concern during elevated temperature application of Ti-based alloys. These problems can principally be avoided by the application of oxidation resistant, alumina forming coatings. In the present paper the possibility of using a Ag-containing TiAl alloy as a coating material for Ti and high-strength gamma-TiAl-alloys is being studied. First, oxidation tests in different environments were carried out, to compare the isothermal and cyclic oxidation resitance of a selected Ag containing coating alloy with that of two, new generation, high strength gamma-titanium aluminides. Subsequently, magnetron sputtering was used to apply the TiAl-Ag coating to a gamma-TiAl alloy (Ti-45Al-8Nb-0.2C) and to pure titanium. The coated materials were tested at 800 degrees centigrade in case of the gamma-TiAl substrate, and at 600 degrees centigrade in case of the Ti substrate. The results illustrate, that the coatings in all studied cases formed a protective alumina surface scale even up to the longest studied test times of 1000 hours. The interdiffusion processes between coating and base material, which eventually determine the coating life, were studied by SEM/EDX investigation after different exposure times.

Słowa kluczowe

PL

pokrycia z tlenkiem glinu; aluminidek tytanu; materiały powlekane; utlenianie; dyfuzja wzajemna; mikrostruktura

EN

alumina forming coatings; titanium aluminides; coated materials; oxidation; interdiffusion; microstructure

• Wydawca: Wydawnictwo SIGMA-NOT
• Czasopismo: Inżynieria Materiałowa
• Rocznik: 2001
• Tom: R. XXII, nr 5
• Strony: 829--833
• Opis fizyczny: Bibliogr. 18 poz., rys.

Twórcy

autor

Singheiser L.

• Forschungszentrum Juelich, Germany

autor

Niewolak L.

• University of Mining and Metallurgy, Kraków, Poland

autor

Shemet V.

• Forschungszentrum Juelich, Germany

autor

Gil A.

• University of Mining and Metallurgy, Kraków, Poland

autor

Quadakkers W.J.

• Forschungszentrum Juelich, Germany

• Forschungszentrum Juelich, Germany

Bibliografia

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