Page 64 - MSAM-1-3

Materials Science in Additive Manufacturing

ORIGINAL RESEARCH ARTICLE
Inconel 718-CoCrMo bimetallic structures

through directed energy deposition-based
additive manufacturing

1
Cory Groden , Victor Champagne , Susmita Bose , Amit Bandyopadhyay *
1
1
2
1 W. M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials
Engineering, Washington State University Pullman, WA 99164, USA
2 US Army Research Laboratory, Weapons and Materials Research Directorate, Aberdeen Proving
Ground, MD, USA

Abstract

Bimetallic structures and coatings through additive manufacturing (AM) have
demonstrated a high degree of freedom for tailoring properties depending on
the application. In this study, Inconel 718 and CoCrMo were used as both are
common alloys and exhibit unique properties, such as high-temperature oxidation,
wear, and fatigue resistance. Using directed energy deposition-based metal AM,
bimetallic structures containing these two alloys were manufactured, and the
resulting structures exhibited no intermetallic phase formation, cracking, or porosity.
Scanning electron microscopy and energy dispersive spectroscopy revealed a
smooth elemental transition between the two compositions. Hardness testing
showed a linear transition in the interfacial zone, validating no brittle intermetallic
*Corresponding author: phase formation. Compression testing and fracture surface analysis revealed that the
Amit Bandyopadhyay
(amitband@wsu.edu) failures were not dependent on the interface properties. High-temperature oxidation
showed no distinct effect on the interface, a firmly attached chromium oxide layer on
Citation: Groden C, Champagne the Inconel 718 side and a loosely attached chromium oxide layer on the CoCrMo
V, Bose S, et al., 2022, Inconel
718-CoCrMo bimetallic structures side. There was also evidence of pit formation on the Inconel 718 surface, but not
through directed energy deposition- on the CoCrMo. These findings confirm a stable bimetallic system in which one of
based additive manufacturing. the two alloys can be used on the other material to improve the structure’s high-
Mater Sci Add Manuf, 1(3):18.
https://doi.org/10.18063/msam.v1i3.18 temperature oxidation or wear/corrosion resistance.
Received: September 1, 2022
Accepted: September 14, 2022 Keywords: Additive manufacturing; Three-dimensional printing; Directed energy
deposition; Cobalt-chromium molybdenum alloy; Inconel 718; Bimetallic structures
Published Online: September 27,
2022
Copyright: © 2022 Author(s).
This is an Open Access article 1. Introduction
distributed under the terms of the
Creative Commons Attribution Advances in metal additive manufacturing (AM) technology have allowed designing
License, permitting distribution,
and reproduction in any medium, multi-material structures to impart unique and site-specific properties for various
provided the original work is applications. For example, AM-processed FeCrAl coating on a Zr alloy increased the
properly cited. oxidation resistance by a factor of 50 . It has been reported that a 30Cr15MoY alloy steel
[1]
[2]
Publisher’s Note: Whoice on a C45 substrate increased the corrosion resistance of neat C45 steel . For strength
Publishing remains neutral with and thermal conductivity, adding a tungsten alloy coating to Inconel 718 increased the
regard to jurisdictional claims in [3]
published maps and institutional strength and thermal conductivity compared to pure Inconel 718 . A GRCop84 coating
[4]
affiliations. on Inconel 718 increased thermal conductivity by 300% more than pure Inconel 718 .
Volume 1 Issue 3 (2022) 1 https://doi.org/10.18063/msam.v1i3.18