Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Influence of successive thermal cycling on microstructure evolution of EBM-manufactured alloy 718 in track-by-track and layer-by-layer design
Department of Engineering Science, University West, Trollhättan, Sweden.
Department of Engineering Science, University West, Trollhättan, Sweden.
Luleå University of Technology, Department of Engineering Sciences and Mathematics, Material Science.ORCID iD: 0000-0001-5921-1935
Department of Engineering Science, University West, Trollhättan, Sweden. Powder Materials & Additive Manufacturing, Swerea KIMAB AB, Kista, Sweden.
Show others and affiliations
2018 (English)In: Materials & design, ISSN 0264-1275, E-ISSN 1873-4197, Vol. 160, p. 427-441Article in journal (Refereed) Published
Abstract [en]

Successive thermal cycling (STC) during multi-track and multi-layer manufacturing of Alloy 718 using electron beam melting (EBM) process leads to a microstructure with a high degree of complexity. In the present study, a detailed microstructural study of EBM-manufactured Alloy 718 was conducted by producing samples in shapes from one single track and single wall to 3D samples with maximum 10 longitudinal tracks and 50 vertical layers. The relationship between STC, solidification microstructure, interdendritic segregation, phase precipitation (MC, δ-phase), and hardness was investigated. Cooling rates (liquid-to-solid and solid-to-solid state) was estimated by measuring primary dendrite arm spacing (PDAS) and showed an increased cooling rate at the bottom compared to the top of the multi-layer samples. Thus, microstructure gradient was identified along the build direction. Moreover, extensive formation of solidification micro-constituents including MC-type carbides, induced by micro-segregation, was observed in all the samples. The electron backscatter diffraction (EBSD) technique showed a high textured structure in 〈001〉 direction with a few grains misoriented at the surface of all samples. Finer microstructure and possibility of more γ″ phase precipitation at the bottom of the samples resulted in slightly higher (~11%) hardness values compared to top of the samples.

Place, publisher, year, edition, pages
Elsevier, 2018. Vol. 160, p. 427-441
Keywords [en]
Electron beam melting, Alloy 718, Track by track, Layer by layer, Successive thermal cycling, Microstructure evolution
National Category
Other Materials Engineering
Research subject
Engineering Materials
Identifiers
URN: urn:nbn:se:ltu:diva-71003DOI: 10.1016/j.matdes.2018.09.038ISI: 000453008100040Scopus ID: 2-s2.0-85053828514OAI: oai:DiVA.org:ltu-71003DiVA, id: diva2:1251260
Note

Validerad;2018;Nivå 2;2018-10-05 (svasva)

Available from: 2018-09-26 Created: 2018-09-26 Last updated: 2019-03-27Bibliographically approved

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textScopus

Authority records

Åkerfeldt, Pia

Search in DiVA

By author/editor
Åkerfeldt, Pia
By organisation
Material Science
In the same journal
Materials & design
Other Materials Engineering

Search outside of DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric score

doi
urn-nbn
Total: 73 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf