Quantification of microstructure in a eutectic high entropy alloy AlCoCrFeNi2.1
Artikel i vetenskaplig tidskrift, 2019

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.

Författare

Adrianna Lozinko

Chalmers, Industri- och materialvetenskap, Material och tillverkning

Oleg V. Mishin

Danmarks Tekniske Universitet (DTU)

Tianbo Yu

Danmarks Tekniske Universitet (DTU)

Uta Klement

Chalmers, Industri- och materialvetenskap, Material och tillverkning

Sheng Guo

Chalmers, Industri- och materialvetenskap, Material och tillverkning

Yubin Zhang

Danmarks Tekniske Universitet (DTU)

IOP Conference Series: Materials Science and Engineering

17578981 (ISSN) 1757899X (eISSN)

Vol. 580 012039

Eutektiska högentropilegeringar : en lovande ny klass av högtemperaturlegeringar

Vetenskapsrådet (VR), 2016-01-01 -- 2020-12-31.

Ämneskategorier

Metallurgi och metalliska material

Styrkeområden

Materialvetenskap

DOI

10.1088/1757-899X/580/1/012039

Mer information

Senast uppdaterat

2020-02-03