Show/Hide Menu
Hide/Show Apps
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Open Science Policy
Open Science Policy
Open Access Guideline
Open Access Guideline
Postgraduate Thesis Guideline
Postgraduate Thesis Guideline
Communities & Collections
Communities & Collections
Help
Help
Frequently Asked Questions
Frequently Asked Questions
Guides
Guides
Thesis submission
Thesis submission
MS without thesis term project submission
MS without thesis term project submission
Publication submission with DOI
Publication submission with DOI
Publication submission
Publication submission
Supporting Information
Supporting Information
General Information
General Information
Copyright, Embargo and License
Copyright, Embargo and License
Contact us
Contact us
Development and directed energy deposition of high strength Hf5Mo15Nb35Ta25Ti20 refractory high entropy alloys
Date
2024-03-01
Author
Özalp, Ali
Okuyucu, Can
Koc, B.
El-Atwani, O.
Aydoğan Güngör, Eda
Metadata
Show full item record
This work is licensed under a
Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
.
Item Usage Stats
111
views
0
downloads
Cite This
In this study, a novel HfMoNbTaTi refractory high entropy alloy was designed by empirical calculations and CALculation of PHAse Diagram (CALPHAD) method by using ThermoCalc software. Directed energy deposition (DED) based additive manufacturing process was used to produce the alloy. After the process parameter determination studies using single-track productions, cuboids were produced. The microstructural investigations showed that while the central region of cuboids has large grains, the outer region has a dendritic structure with some unmolten Mo powders. Although columnar grain formation, which is the general characteristic of directional solidification, was observed at some points, irregularly shaped grains were dominant in the structure. Moreover, there were micron to nano-sized Hf-Ti-O particles inside the grains and especially around the grain boundaries. X-ray diffraction (XRD) and transmission electron microscopy (TEM) analyses confirmed the formation of disordered body-centered cubic (BCC) Hf5Mo15Nb35Ta25Ti20 alloy with ∼6 vol% of Hf-Ti-O particles. Electron backscatter diffraction (EBSD) analyses indicated that there is a slight texture in the building direction along 〈111〉. In order to determine the stability of these alloys, ex-situ heat treatments coupled with XRD studies were conducted. As opposed to CALPHAD calculations it was not observed any HCP phase formation. Compression test results showed that Hf5Mo15Nb35Ta25Ti20 alloys have high strength (σy = ∼1300 MPa) and high compressive ductility with good strain-hardening ability. Theoretical calculations revealed that the strength of the alloy mainly originated from solid solution strengthening.
Subject Keywords
Additive manufacturing
,
CALPHAD
,
Compression test
,
Directed energy deposition
,
Phase stability
,
Refractory high entropy alloys (RHEAs)
URI
https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85183205973&origin=inward
https://hdl.handle.net/11511/108633
Journal
Materials Characterization
DOI
https://doi.org/10.1016/j.matchar.2024.113679
Collections
Department of Metallurgical and Materials Engineering, Article
Citation Formats
IEEE
ACM
APA
CHICAGO
MLA
BibTeX
A. Özalp, C. Okuyucu, B. Koc, O. El-Atwani, and E. Aydoğan Güngör, “Development and directed energy deposition of high strength Hf5Mo15Nb35Ta25Ti20 refractory high entropy alloys,”
Materials Characterization
, vol. 209, pp. 0–0, 2024, Accessed: 00, 2024. [Online]. Available: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85183205973&origin=inward.