Transmission electron microscopy of a CMSX-4 Ni-base superalloy produced by selective electron beam melting

Parsa AB, Ramsperger M, Kostka A, Somsen C, Körner C, Eggeler G (2016)

Publication Language: English

Publication Status: Published

Publication Type: Journal article, Original article

Publication year: 2016

Journal

Metals MDPI

Publisher: MDPI AG

Book Volume: 6

Article Number: 258

Journal Issue: 11

DOI: 10.3390/met6110258

Abstract

In this work, the microstructures of superalloy specimens produced using selective electron beam melting additive manufacturing were characterized. The materials were produced using a CMSX-4 powder. Two selective electron beam melting processing strategies, which result in higher and lower effective cooling rates, are described. Orientation imaging microscopy, scanning transmission electron microscopy and conventional high resolution transmission electron microscopy are used to investigate the microstructures. Our results suggest that selective electron beam melting processing results in near equilibrium microstructures, as far as γ′ volume fractions, the formation of small amounts of TCP phases and the partitioning behavior of the alloy elements are concerned. As expected, higher cooling rates result in smaller dendrite spacings, which are two orders of magnitude smaller than observed during conventional single crystal casting. During processing, columnar grains grow in <100> directions, which are rotated with respect to each other. There are coarse γ/γ′ microstructures in high angle boundary regions. Dislocation networks form low angle boundaries. A striking feature of the as processed selective electron beam melting specimens is their high dislocation density. From a fundamental point of view, this opens new possibilities for the investigation of elementary dislocation processes which accompany solidification.

Authors with CRIS profile

Markus Ramsperger Lehrstuhl für Werkstoffwissenschaften (Werkstoffkunde und Technologie der Metalle) Carolin Körner Lehrstuhl für Werkstoffwissenschaften (Werkstoffkunde und Technologie der Metalle)

Related research project(s)

Activity SEBM of special alloys Jan. 1, 2000 - Jan. 1, 2003 Activity Development of process strategies Jan. 1, 2000 - Jan. 1, 2003

Involved external institutions

Ruhr-Universität Bochum (RUB) DE Germany (DE) Max-Planck-Institut für Eisenforschung GmbH (MPIE) / Max Planck Institute for Iron Research DE Germany (DE)

How to cite

APA:

Parsa, A.B., Ramsperger, M., Kostka, A., Somsen, C., Körner, C., & Eggeler, G. (2016). Transmission electron microscopy of a CMSX-4 Ni-base superalloy produced by selective electron beam melting. Metals, 6(11). https://dx.doi.org/10.3390/met6110258

MLA:

Parsa, Alireza B., et al. "Transmission electron microscopy of a CMSX-4 Ni-base superalloy produced by selective electron beam melting." Metals 6.11 (2016).

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