Characterization of primary microstructure of γ–γʹ Co–Al–W cobalt-based superalloy

• Autorzy: Mikuszewski T. , Tomaszewska A. , Moskal G. , Migas D. , Niemiec D.

Identyfikatory

DOI

10.15199/28.2017.5.3

Warianty tytułu

PL

Charakterystyka mikrostruktury pierwotnej nadstopu kobaltu Co–Al–W typu γ–γʹ

• Języki publikacji: EN

Abstrakty

EN

Present paper concerns primary structure of cobalt-based superalloys Co–9Al–9W with γ/γʹ structure, casted via induction melting process. Common problems described in literature, concerning difficulties in obtaining uniform distribution of tungsten, particularly in interdendritic areas were reason of utilization of modified casting process. Alter method is based on tungsten dosing into liquid metal bath of cobalt and aluminium during melting. This method allows to obtain microstructure characterized by considerably decreased microsegregation, especially in case of tungsten. This type of primary structure results in simplified and more economical homogenization performance of casts before further technological processes. Used method of casting give the possibility to obtain samples with small effect of segregations of alloying elements. Observed effect of interdendritic segregations were related to higher level of aluminium concentration and lower cobalt, but in both cases the measured difference was 2 to 4 % at.

PL

Celem artykułu jest charakterystyka mikrostruktury pierwotnej stopu Co–9Al–9W w stanie bezpośrednio po odlaniu, z uwzględnieniem rozmieszczenia składników stopowych w rdzeniach dendrytów i obszarach międzydendrytycznych w różnych strefach odlewu oraz profilu mikrotwardości. Ważną kwestią była jednorodność rozmieszczenia wolframu w obszarach rdzeni dendrytów i w przestrzeniach międzydendrytycznych, co jest typowym problemem w stopach z dodatkiem wolframu.

Słowa kluczowe

EN

Co–Al–W alloy; primary microstructure; casting process

PL

stop Co-9Al-9W; nadstopy kobaltu typu γ-γʹ; struktura pierwotna; proces odlewania

• Wydawca: Wydawnictwo SIGMA-NOT
• Czasopismo: Inżynieria Materiałowa
• Rocznik: 2017
• Tom: Vol. 38, nr 5
• Strony: 217--223
• Opis fizyczny: Bibliogr. 27 poz., fig., tab.

Twórcy

autor

Mikuszewski T.

• Silesian University of Technology, Institute of Materials Engineering, Katowice

autor

Tomaszewska A.

• Silesian University of Technology, Institute of Materials Engineering, Katowice

autor

Moskal G.

• Silesian University of Technology, Institute of Materials Engineering, Katowice

autor

Migas D.

• Silesian University of Technology, Institute of Materials Engineering, Katowice

autor

Niemiec D.

• Silesian University of Technology, Institute of Materials Engineering, Katowice

Bibliografia

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Uwagi

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).