Degradation of Creep Resistant Ni - alloy During Aging at Elevated Temperature Part II: Structure Investigations

• Autorzy: Kaczorowski M. , Skoczylas P. , Krzyńska A.

Identyfikatory

DOI

10.1515/afe-2015-0077

• Języki publikacji: EN

Abstrakty

EN

The results of structure observations of Ni base superalloy subjected to long-term influence of high pressure hydrogen atmosphere at 750K and 850K are presented. The structure investigation were carried out using conventional light-, scanning- (SEM) and transmission electron microscopy (TEM). The results presented here are supplementary to the mechanical studies given in part I of this investigations. The results of study concerning mechanical properties degradation and structure observations show that the differences in mechanical properties of alloy subjected different temperature are caused by more advanced processes of structure degradation during long-term aging at 850K, compare to that at 750K. Higher service temperature leads to formation of large precipitates of δ phase. The nucleation and growth of needle- and/or plate-like, relative large delta precipitates proceed probably at expense strengthening γ" phases. Moreover, it can't be excluded that the least stable γ" phase is replaced with more stable γ' precipitates. TEM observations have disclosed differences in dislocation structure of alloy aged at 750K and 850K. The dislocation observed in alloy subjected to 750K are were seldom observed only, while in that serviced at high stress and 850K dislocation array and dislocation cell structure was typical.

Słowa kluczowe

EN

Ni-base superalloy; structure investigations; SEM observation; TEM observation

PL

nadstop niklu; badanie struktury; obserwacja SEM; obserwacja TEM

• Wydawca: Komisja Odlewnictwa Polskiej Akademii Nauk Oddział w Katowicach
• Czasopismo: Archives of Foundry Engineering
• Rocznik: 2015
• Tom: Vol. 15, iss. 4
• Strony: 45--50
• Opis fizyczny: Bibliogr. 10 poz., rys.

Twórcy

autor

Kaczorowski M.

• Institute of Mechanics and Printing, Warsaw University of Technology, Narbutta 85, 02-524 Warszawa, Poland

autor

Skoczylas P.

• Institute of Mechanics and Printing, Warsaw University of Technology, Narbutta 85, 02-524 Warszawa, Poland

autor

Krzyńska A.

• Institute of Manufacturing Technology, Faculty of Production Engineering, Warsaw University of Technology, Narbutta 85, 02-524 Warszawa, Poland

Bibliografia

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