The equiatomic CrMnFeCoNi high entropy alloy is additively manufactured by the laser engineered net shaping (LENSTM) process, and the solidification conditions, phase formation, as-deposited microstructures, and tensile behavior are investigated. The LENSTM-deposited CrMnFeCoNi alloy exhibits a single-phase disordered face centered cubic (FCC) structure, as evidenced by X-ray diffraction (XRD), and rationalized by Scheil's solidification simulation. Furthermore, microstructures at multiple length scales, i.e. columnar grains, solidification substructures, and dislocation substructures, are formed. The tensile deformation process is mainly accommodated by dislocation activities with the assistance of deformation twinning. The tensile yield strength of the LENSTM-deposited CrMnFeCoNi alloy is comparable to that of finer-grained wrought-annealed counterparts, due to the additional initial-dislocation strengthening. However, the uniform tensile elongation, by contrast, is lowered, which is attributed to the increased dynamic dislocation recovery rate and hence the weakened work hardening capability of the LENSTM-deposited CrMnFeCoNi. This study demonstrates the capability of the LENSTM process for manufacturing the CrMnFeCoNi alloy, with high performance, for engineering applications. © 2019 Elsevier B.V.

Additive manufacturing of fine-grained and dislocation-populated CrMnFeCoNi high entropy alloy by laser engineered net shaping

Berto Filippo;
2019

Abstract

The equiatomic CrMnFeCoNi high entropy alloy is additively manufactured by the laser engineered net shaping (LENSTM) process, and the solidification conditions, phase formation, as-deposited microstructures, and tensile behavior are investigated. The LENSTM-deposited CrMnFeCoNi alloy exhibits a single-phase disordered face centered cubic (FCC) structure, as evidenced by X-ray diffraction (XRD), and rationalized by Scheil's solidification simulation. Furthermore, microstructures at multiple length scales, i.e. columnar grains, solidification substructures, and dislocation substructures, are formed. The tensile deformation process is mainly accommodated by dislocation activities with the assistance of deformation twinning. The tensile yield strength of the LENSTM-deposited CrMnFeCoNi alloy is comparable to that of finer-grained wrought-annealed counterparts, due to the additional initial-dislocation strengthening. However, the uniform tensile elongation, by contrast, is lowered, which is attributed to the increased dynamic dislocation recovery rate and hence the weakened work hardening capability of the LENSTM-deposited CrMnFeCoNi. This study demonstrates the capability of the LENSTM process for manufacturing the CrMnFeCoNi alloy, with high performance, for engineering applications. © 2019 Elsevier B.V.
File allegati a questo prodotto
File Dimensione Formato  
Guan_additive-manufacturing-finegrained_2019.pdf

solo gestori archivio

Tipologia: Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 4.41 MB
Formato Adobe PDF
4.41 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11573/1654379
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 59
  • ???jsp.display-item.citation.isi??? 51
social impact