Publication detail

Tailoring a Refractory High Entropy Alloy by Powder Metallurgy Process Optimization

MORAVČÍKOVÁ DE ALMEIDA GOUVEA, L. MORAVČÍK, I. POUCHLÝ, V. KOVÁČOVÁ, Z. KITZMANTEL, M. NEUBAUER, E. DLOUHÝ, I.

Original Title

Tailoring a Refractory High Entropy Alloy by Powder Metallurgy Process Optimization

Type

journal article in Web of Science

Language

English

Original Abstract

This paper reports the microstructural evolution and mechanical properties of a low-density Al0.3NbTa0.8Ti1.5V0.2Zr refractory high-entropy alloy (RHEA) prepared by means of a combination of mechanical alloying and spark plasma sintering (SPS). Prior to sintering, the morphology, chemical homogeneity and crystal structures of the powders were thoroughly investigated by varying the milling times to find optimal conditions for densification. The sintered bulk RHEAs were produced with diverse feedstock powder conditions. The microstructural development of the materials was analyzed in terms of phase composition and constitution, chemical homogeneity, and crystallographic properties. Hardness and elastic constants also were measured. The calculation of phase diagrams (CALPHAD) was performed to predict the phase changes in the alloy, and the results were compared with the experiments. Milling time seems to play a significant role in the contamination level of the sintered materials. Even though a protective atmosphere was used in the entire manufacturing process, carbide formation was detected in the sintered bulks as early as after 3 h of powder milling. Oxides were observed after 30 h due to wear of the high-carbon steel milling media and SPS consolidation. Ten hours of milling seems sufficient for achieving an optimal equilibrium between microstructural homogeneity and refinement, high hardness and minimal contamination.

Keywords

refractory complex concentrated alloys; microstructures; mechanical alloying; spark plasma sintering; mechanical properties

Authors

MORAVČÍKOVÁ DE ALMEIDA GOUVEA, L.; MORAVČÍK, I.; POUCHLÝ, V.; KOVÁČOVÁ, Z.; KITZMANTEL, M.; NEUBAUER, E.; DLOUHÝ, I.

Released

1. 10. 2021

Publisher

MDPI

Location

BASEL

ISBN

1996-1944

Periodical

Materials

Year of study

14

Number

19

State

Swiss Confederation

Pages from

1

Pages to

21

Pages count

21

URL

https://www.mdpi.com/1996-1944/14/19/5796

Full text in the Digital Library

http://hdl.handle.net/11012/203069

BibTex

@article{BUT174953,
  author="Larissa {Moravčíková de Almeida Gouvea} and Igor {Moravčík} and Václav {Pouchlý} and Zuzana {Kováčová} and Michael {Kitzmantel} and Erich {Neubauer} and Ivo {Dlouhý}",
  title="Tailoring a Refractory High Entropy Alloy by Powder Metallurgy Process Optimization",
  journal="Materials",
  year="2021",
  volume="14",
  number="19",
  pages="1--21",
  doi="10.3390/ma14195796",
  issn="1996-1944",
  url="https://www.mdpi.com/1996-1944/14/19/5796"
}