Cryogenic tensile behavior of laser additive manufactured CoCrFeMnNi high entropy alloys

被引：32

作者：

Kim, Eun Seong ^{[1
]}

Ramkumar, K. R. ^{[2
]}

Karthik, G. M. ^{[3
]}

Jeong, Sang Guk ^{[1
]}

Ahn, Soung Yeoul ^{[1
]}

Sathiyamoorthi, Praveen ^{[4
]}

Park, Hyojin ^{[1
]}

Heo, Yoon-Uk ^{[2
]}

Kim, Hyoung Seop ^{[2
,5
]}

机构：

[1] Pohang Univ Sci & Technol POSTECH, Dept Mat Sci & Engn, Pohang 37673, South Korea

[2] Pohang Univ Sci & Technol POSTECH, Grad Inst Ferrous & Energy Mat Technol GIFT, Pohang 37673, South Korea

[3] Indian Inst Technol BHU, Dept Mech Engn, Varanasi 221005, India

[4] Indian Inst Technol BHU, Dept Met Engn, Varanasi 221005, India

[5] Tohoku Univ, Adv Inst Mat Res WPI AIMR, Sendai 9808577, Japan

来源：

JOURNAL OF ALLOYS AND COMPOUNDS | 2023年 / 942卷

基金：

新加坡国家研究基金会;

关键词：

Laser powder bed fusion; Direct energy deposition; High entropy alloy; Cryogenic tensile properties; Deformation twinning; MECHANICAL-PROPERTIES; METALLIC COMPONENTS; MICROSTRUCTURE; DEFORMATION; EVOLUTION; STRENGTH; CRMNFECONI; DUCTILITY; STRESS;

D O I：

10.1016/j.jallcom.2023.169062

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

In the present work the microstructural evolution, tensile properties, and deformation behavior of addi-tively manufactured equiatomic CoCrFeMnNi high entropy alloy (HEA) were investigated at a cryogenic temperature (77 K). Metal additive manufacturing components are known to have exceptional yield strength, without compromising ductility. Here, laser powder bed fusion (LPBF) and direct energy de-position (DED) additive manufacturing processes were chosen as the fabrication techniques and wrought CoCrFeMnNi HEA was also fabricated for comparison. The tensile behaviors at different temperatures (298 K and 77 K) indicated temperature-dependent strength and ductility in all the samples. In particular, the HEA processed by DED exhibited excellent strength and ductility, with exceptional strain hardening, compared to the LPBF and wrought samples at 77 K. Post-tensile microstructures revealed the formation of de-formation twinning in addition to dislocation slip as deformation mechanism at 77 K. Our results suggest that cellular structure plays an essential role in yield strength. Moreover, the interactions of the deformation twins and cellular dislocation structures increase strain hardening and help retard plastic instability, thereby improving ductility at 77 K.(c) 2023 Elsevier B.V. All rights reserved.

引用

页数：15

共 68 条

[1] Understanding grain evolution in additive manufacturing through modeling [J].