Thermodynamic study of single crystal, Ni-based superalloys in the γ plus γ′ two-phase region using Knudsen Effusion Mass Spectrometry, DSC and SEM

JOURNAL OF ALLOYS AND COMPOUNDS

卷:870

Article

Spathara, Dimitra¹  Sergeev, Dmitry²  Kobertz, Dietmar²  Mueller, Michael²  Putman, Duncan³  Warnken, Nils¹ 

[1] Univ Birmingham, Sch Met & Mat, Birmingham B15 2TT, W Midlands, England

[2] Forschungszentrum Julich, Inst Energy & Climate Res IEK 2, D-52425 Julich, Germany

[3] Rolls Royce PLC, Derby DE24 8BJ, England

关键词: Activity;    Sublimation;    Vaporisation;    Knudsen effusion mass spectrometry;    High-temperature alloys;    Gas-solid reactions;   

DOI  :  10.1016/j.jallcom.2021.159295

来源: Elsevier

【 摘 要 】

Second and third generation single crystal (SX) Ni-based superalloys are considered to be sensitive to microsegregation, incipient melting and microstructural instability. Thus, their thermodynamic properties and stability at high temperatures are of key importance. Vapour composition consisting of four species has been detected in the temperature range 1453-1573 K. This was found after studies of three single crystal Nibased superalloys CMSX-4, CMSX-10K (R) and CMSX-10N (R) using the method of Knudsen Effusion Mass Spectrometry (KEMS). The activities of Ni, Co, Cr, and Al have been determined in the gamma+gamma', two-phase region. A series of Differential Scanning Calorimetry (DSC) measurements were carried out at various ramping up rates to determine phase transition temperatures; the gamma' solvus, the solidus and the liquidus temperature were obtained. Back-scattered Electron Imaging (BEI) and Energy Dispersive Spectroscopy (EDS) measurements were performed and depicted the effect post KEMS for such complex multicomponent systems. (c) 2021 Elsevier B.V. All rights reserved.

【 授权许可】

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