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  • Additively manufactured Ni-20Cr to V functionally graded material: Computational predictions and experimental verification of phase formations
Title: Additively manufactured Ni-20Cr to V functionally graded material: Computational predictions and experimental verification of phase formations
A database for the Cr-Ni-V system was constructed by modeling the binary Cr-V and ternary Cr-Ni-V systems using the CALPHAD approach aided by density functional theory (DFT)-based first-principles calculations and ab initio molecular dynamics (AIMD) simulations. To validate this new database, a functionally graded material (FGM) using Ni-20Cr and V was fabricated using directed energy deposition additive manufacturing (DED AM) and experimentally characterized. The deposited Ni-20Cr was pure fcc phase, while increasing V content across the gradient resulted in sigma phase formation, followed by bcc phase formation. The experimentally measured phases were compared with CALPHAD computations made using a Cr-Ni-V thermodynamic database from the literature and the database developed in the present work. The newly developed database was shown to better predict the experimentally observed phases due to its accurate modeling of binary systems within the database and the ternary liquid phase, which is critical for accurate Scheil calculations.  more » « less
Award ID(s):
2050069
PAR ID:
10496304
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Journal of Alloys and Compounds
Volume:
985
Issue:
C
ISSN:
0925-8388
Page Range / eLocation ID:
174011
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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