Quantification of microstructure in a eutectic high entropy alloy AlCoCrFeNi2.1

Adrianna Lozinko, Oleg V. Mishin, Tianbo Yu, Uta Klement, Sheng Guo, Yubin Zhang*

*Corresponding author for this work

Research output: Contribution to journalConference articleResearchpeer-review

16 Downloads (Pure)

Abstract

Eutectic high entropy alloys (EHEAs) are a new class of metallic alloys with good mechanical properties at various temperatures. In the present investigation, microstructural parameters such as the volume fraction of two phases (FCC (L12) and BCC (B2)) forming the eutectic, the orientation relationship between these phases and interphase boundary spacings in as-cast EHEA AlCoCrFeNi2.1 were quantified using electron microscopy. It is found that the two phases have a Kurdjumov-Sachs orientation relationship, i.e., {111}fcc || {110}bcc and ⟨110⟩fcc || ⟨111⟩bcc. It is also found that both regular semi-coherent lamellar and irregular curved interphase boundaries are present within individual eutectic colonies. The habit planes for the semi-coherent lamellar interfaces are {224} and {123} for the FCC and BCC phases, respectively. Quantitative microstructural analysis shows that the ratio of volume fractions of the FCC and BCC phases within the regular lamellar regions differs to that within irregular regions, which suggests a local chemistry difference between the two regions. Finally, the solidification process of EHEAs is discussed, and possible ways to optimize the mechanical properties by microstructural design are suggested.
Original languageEnglish
Article number012039
JournalI O P Conference Series: Materials Science and Engineering
Volume580
Issue number1
Number of pages6
ISSN1757-8981
DOIs
Publication statusPublished - 2019
Event40th Risø International Symposium on Material Science: Metal Microstructures in 2D, 3D, and 4D - Roskilde, Denmark
Duration: 2 Sep 20196 Sep 2019

Conference

Conference40th Risø International Symposium on Material Science: Metal Microstructures in 2D, 3D, and 4D
CountryDenmark
CityRoskilde
Period02/09/201906/09/2019

Bibliographical note

GA no. 788567

Cite this