Microstructural characterization of gas phase aluminized TiAlCrNb intermetallic alloy

• Autorzy: Moskal G. , Góral M. , Swadźba L. , Mendala B. , Hetmańczyk M. , Witala B.

Warianty tytułu

PL

Charakterystyka mikrostruktury stopu TiAlCrNb po procesie aluminiowania gazowego

• Języki publikacji: EN

Abstrakty

EN

This article presents a microstructure characterization of an alloy coating based on Ti-48Al-2Cr-2Nb- type γ + α2 intermetallic phases deposited via an out-of-pack aluminizing process. The goal of the aluminizing process was to obtain a coating composed of aluminum-rich TiAl2 or TiAl3 phases with greater oxidation resistance compared to the base alloy. The results showed that the gas-phase aluminizing process produced a coating with specific microstructural properties. The thickness of the layer obtained, including the transition zone, was approximately 20µm. X-ray diffraction (XRD) phase composition studies demonstrated that the outer coating zone was primarily composed of a TiAl2 phase, and its thickness was approximately 10 µm. Microanalysis of the chemical composition showed that, in addition to the main components, i.e. titanium and aluminum, chromium and niobium were present in the outer coating. Electron backscatter diffraction (EBSD) studies further indicated the probable presence of a TiAl2 phase. The coating obtained was of good quality, and cracks or pores, which are typical of coatings obtained via powder methods, were not detected.

PL

W artykule przedstawiono wyniki badań mikrostruktury warstwy wierzchniej stopu na osnowie faz międzymetalicznych γ + α2 typu Ti-48Al-2Cr-2Nb po procesie aluminiowania metodą out-of-pack. Celem procesu aluminiowania było uzyskanie warstwy zewnętrznej zbudowanej z bogatych w aluminium faz typu TiAi2 lub TiAl3 o wyższej odporności na utlenianie w porównaniu do stopu podłoża. Zrealizowane badania wykazały, że zastosowanie metody aluminiowania gazowego pozwoliło na wytworzenie na powierzchni stopu pokrycia o zakładanych właściwościach mikrostrukturalnych. Grubość otrzymanej warstwy, łącznie ze strefą przejściową wynosiła ok. 20 µm. Mikroanaliza składu chemicznego wykazała również, że poza głónymi składnikami tj. tytanem i aluminium w obszarze tym obecne były również chrom i niob. Badania EBSD wykazały ponadto prawdopodobną obecność fazy Ti3Al5. Uzyskane pokrycie było dobrej jakości, nie stwierdzono pęknięć ani pustek, typowych dla warstw otrzymanych metodami proszkowymi.

Słowa kluczowe

EN

coatings; microstructure characterization; titanium aluminides; EBSD

PL

powłoki; charakterystyka mikrostruktury; aluminiowanie gazowe; EBSD

• Wydawca: Institute of Metallurgy and Materials Science of Polish Academy of Sciences ; Committee of Materials Engineering and Metallurgy of Polish Academy of Sciences
• Czasopismo: Archives of Metallurgy and Materials
• Rocznik: 2012
• Tom: Vol. 57, iss. 1
• Strony: 253--259
• Opis fizyczny: Bibliogr. 20 poz., rys., tab.

Twórcy

autor

Moskal G.

autor

Góral M.

autor

Swadźba L.

autor

Mendala B.

autor

Hetmańczyk M.

autor

Witala B.

• Department of Materials Science, Silesian University of Technology, 40-019 Katowice, 8 Krasinskiego Str., Poland

Bibliografia

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