Research Papers

Selective Laser Melting of Graphene-Reinforced Inconel 718 Superalloy: Evaluation of Microstructure and Tensile Performance

[+] Author and Article Information
Yachao Wang

Department of Mechanical and
Materials Engineering,
University of Cincinnati,
598 Rhodes Hall,
P.O. Box 210072,
Cincinnati, OH 45221
e-mail: wang3yc@mail.uc.edu

Jing Shi

Department of Mechanical and
Materials Engineering,
University of Cincinnati,
598 Rhodes Hall,
P.O. Box 210072,
Cincinnati, OH 45221
e-mail: jing.shi@uc.edu

Shiqiang Lu

School of Aeronautical
Manufacturing Engineering,
Nanchang Hangkong University,
696 Fenghe Road South,
Nanchang, Jiangxi 330063, China
e-mail: niatlusq@126.com

Yun Wang

School of Aircraft Engineering,
Nanchang Hangkong University,
696 Fenghe Road South,
Nanchang, Jiangxi 330063, China
e-mail: wangyun66@126.com

1Corresponding author.

Contributed by the Manufacturing Engineering Division of ASME for publication in the JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING. Manuscript received August 17, 2016; final manuscript received September 12, 2016; published online October 18, 2016. Editor: Y. Lawrence Yao.

J. Manuf. Sci. Eng 139(4), 041005 (Oct 18, 2016) (6 pages) Paper No: MANU-16-1439; doi: 10.1115/1.4034712 History: Received August 17, 2016; Revised September 12, 2016

Graphene nanoplatelets (GNPs) have many outstanding properties, such as high mechanical strengths, light weight, and high electric conductivity. These unique properties make it an ideal reinforcement used for metal matrix composites (MMCs). In the past few years, many studies have been performed to incorporate GNPs into metal matrix and investigate the properties of obtained metal matrix composites. Meanwhile, fabrication of MMCs through laser-assisted additive manufacturing (LAAM) has attracted much attention in recent years due to the advantages of low waste, high precision, short production lead time, and high workpiece complexity capability. In this study, the two attractive features are combined to produce GNPs reinforced MMC using selective laser melting (SLM) process, one of the LAAM processes. The target metal matrix material is Inconel 718, a nickel-based Ni–Cr–Fe austenitic superalloy that possesses excellent workability and mechanical performance, and has wide applications in industries. In the experiment, pure Inconel 718 and GNPs reinforced Inconel 718 composites with two levels of GNPs content (i.e., 0.25 and 1 wt. %) are obtained by SLM. Note that before the SLM process, a novel powder mixture procedure is employed to ensure the even dispersion of GNPs in the Inconel 718 powders. Room temperature tensile tests are conducted to evaluate the tensile properties. Scanning electron microscopy (SEM) observations are conducted to analyze the fracture surface of materials and to understand the reinforcing mechanism. It is found that fabrication of GNPs reinforced MMC using SLM is a viable approach. The obtained composite possesses dense microstructure and significantly enhanced tensile strength. The ultimate tensile strengths (UTSs) are 997.8, 1296.3, and 1511.6 MPa, and the Young's moduli are 475, 536, and 675 GPa, for 0 wt. % (pure Inconel 718), 0.25 wt. %, and 1 wt. % GNP additions, respectively. The bonding between GNPs and matrix material appears to be strong, and GNPs could be retained during the SLM process. The strengthening effect and mechanisms involved in the composites are discussed. Load transfer, thermal expansion coefficient mismatch, and dislocation hindering are believed to be the three main reinforcing mechanisms involved. It should be noted that more work needs to be conducted in the future to obtain more comprehensive information regarding other static and dynamic properties and the high-temperature performances of the GNP-reinforced MMCs produced by SLM. Process parameter optimization should also be investigated.

Copyright © 2017 by ASME
Your Session has timed out. Please sign back in to continue.


Jacobson, D. M. , and Bennett, G. , 2006, “ Practical Issues in the Application of Direct Metal Laser Sintering,” Solid Freeform Fabrication Symposium, Austin, TX, Aug. 14–16, pp. 728–739.
Mercelis, P. , and Kruth, J. P. , 2006, “ Residual Stresses in Selective Laser Sintering and Selective Laser Melting,” Rapid Prototyping J., 12(5), pp. 254–265. [CrossRef]
Haga, S. , Harada, Y. , and Tsubakino, H. , 2006, “ Fatigue Life Prolongation of Carburized Steel by Means of Shot-Peening,” Materials Sci. Forum, 505–507, pp. 775–780. [CrossRef]
Thomas, A. , El-Wahabi, M. , Cabrera, J. M. , and Prado, J. M. , 2006, “ High Temperature Deformation of Inconel 718,” J. Mater. Process. Technol., 177(1), pp. 469–472. [CrossRef]
Sundararaman, M. , Mukhopadhyay, P. , and Banerjee, S. , 1988, “ Precipitation of the δ-Ni3Nb Phase in Two Nickel Base Superalloys,” Metall. Trans. A, 19(3), pp. 453–465. [CrossRef]
Sundararaman, M. , Mukhopadhyay, P. , and Banerjee, S. , 1994, “ Precipitation and Room Temperature Deformation Behaviour of Inconel 718,” Superalloys 718, 625, 706 and Various Derivatives, E. A. Loria , ed., The Minerals, Metals and Materials Society, Pittsburgh, PA, pp. 419–440.
Paul, C. P. , Ganesh, P. , Mishra, S. K. , Bhargava, P. , Negi, J. , and Nath, A. K. , 2007, “ Investigating Laser Rapid Manufacturing for Inconel-625 Components,” Opt. Laser Technol., 39(4), pp. 800–805. [CrossRef]
Parimi, L. L. , Clark, D. , and Attallah, M. M. , 2014, “ Microstructural and Texture Development in Direct Laser Fabricated IN718,” Mater. Charact., 89, pp. 102–111. [CrossRef]
Cooper, D. E. , Blundell, N. , Maggs, S. , and Gibbons, G. J. , 2013, “ Additive Layer Manufacture of Inconel 625 Metal Matrix Composites, Reinforcement Material Evaluation,” J. Mater. Process. Technol., 213(12), pp. 2191–2200. [CrossRef]
Hong, C. , Gu, D. , Dai, D. , Gasser, A. , Weisheit, A. , Kelbassa, I. , and Poprawe, R. , 2013, “ Laser Metal Deposition of TiC/Inconel 718 Composites With Tailored Interfacial Microstructures,” Opt. Laser Technol., 54, pp. 98–109. [CrossRef]
Gu, D. , Hong, C. , Jia, Q. , Dai, D. , Gasser, A. , Weisheit, A. , and Poprawe, R. , 2014, “ Combined Strengthening of Multi-Phase and Graded Interface in Laser Additive Manufactured TiC/Inconel 718 Composites,” J. Phys. D, 47(4), p. 045309. [CrossRef]
Bi, G. , Sun, C. N. , Nai, M. L. , and Wei, J. , 2013, “ Micro-Structure and Mechanical Properties of Nano-TiC Reinforced Inconel 625 Deposited Using LAAM,” Phys. Proc., 41, pp. 828–834. [CrossRef]
Jang, B. , and Zhamu, A. , 2008, “ Processing of Nanographene Platelets (NGPs) and NGP Nanocomposites: A Review,” J. Mater. Sci., 43(15), pp. 5092–5101. [CrossRef]
Wang, J. , Li, Z. , Fan, G. , Pan, H. , Chen, Z. , and Zhang, D. , 2012, “ Reinforcement With Graphene Nanosheets in Aluminum Matrix Composites,” Scr. Mater., 66(8), pp. 594–597. [CrossRef]
Chen, L. Y. , Konishi, H. , Fehrenbacher, A. , Ma, C. , Xu, J. Q. , Choi, H. , and Li, X. C. , 2012, “ Novel Nanoprocessing Route for Bulk Graphene Nanoplatelets Reinforced Metal Matrix Nanocomposites,” Scr. Mater., 67(1), pp. 29–32. [CrossRef]
Bastwros, M. , Kim, G. Y. , Zhu, C. , Zhang, K. , Wang, S. , Tang, X. , and Wang, X. , 2014, “ Effect of Ball Milling on Graphene Reinforced Al6061 Composite Fabricated by Semi-Solid Sintering,” Composites, Part B, 60, pp. 111–118. [CrossRef]
Rashad, M. , Pan, F. , Asif, M. , and Tang, A. , 2014, “ Powder Metallurgy of Mg–1% Al–1% Sn Alloy Reinforced With Low Content of Graphene Nanoplatelets (GNPs),” J. Ind. Eng. Chem., 20(6), pp. 4250–4255. [CrossRef]
Tang, Y. , Yang, X. , Wang, R. , and Li, M. , 2014, “ Enhancement of the Mechanical Properties of Graphene–Copper Composites With Graphene–Nickel Hybrids,” Mater. Sci. Eng. A, 599, pp. 247–254. [CrossRef]
Peng, Y. , Hu, Y. , Han, L. , and Ren, C. , 2014, “ Ultrasound-Assisted Fabrication of Dispersed Two-Dimensional Copper/Reduced Graphene Oxide Nanosheets Nanocomposites,” Composites, Part B, 58, pp. 473–477. [CrossRef]
Lin, D. , Liu, C. R. , and Cheng, G. J. , 2014, “ Single-Layer Graphene Oxide Reinforced Metal Matrix Composites by Laser Sintering: Microstructure and Mechanical Property Enhancement,” Acta Mater., 80, pp. 183–193. [CrossRef]
Manfredi, D. , Ambrosio, E. P. , Calignano, F. , Krishnan, M. , Canali, R. , Biamino, S. , and Badini, C. , 2013, “ Direct Metal Laser Sintering: An Additive Manufacturing Technology Ready to Produce Lightweight Structural Parts for Robotic Applications,” Metall. Ital., 10, pp. 15–24.
Yoon, D. , Son, Y. W. , and Cheong, H. , 2011, “ Negative Thermal Expansion Coefficient of Graphene Measured by Raman Spectroscopy,” Nano Lett., 11(8), pp. 3227–3231. [CrossRef] [PubMed]
Fattahi, M. , Gholami, A. R. , Eynalvandpour, A. , Ahmadi, E. , Fattahi, Y. , and Akhavan, S. , 2014, “ Improved Microstructure and Mechanical Properties in Gas Tungsten Arc Welded Aluminum Joints by Using Graphene Nanosheets/Aluminum Composite Filler Wires,” Micron, 64, pp. 20–27. [CrossRef] [PubMed]
Rashad, M. , Pan, F. , Tang, A. , and Asif, M. , 2014, “ Effect of Graphene Nanoplatelets Addition on Mechanical Properties of Pure Aluminum Using a Semi-Powder Method,” Prog. Nat. Sci. Mater. Int., 24(2), pp. 101–108. [CrossRef]


Grahic Jump Location
Fig. 1

Inconel 718 powder mixed with 0.25 wt. % graphene

Grahic Jump Location
Fig. 2

Close-up view of SLM process

Grahic Jump Location
Fig. 3

Dimension of tensile test specimens

Grahic Jump Location
Fig. 4

As-built tensile specimens

Grahic Jump Location
Fig. 5

Optical micrographs of SLMed GNPs reinforced Inconel 718 on the cross sections parallel to (a) build direction and (b) scanning plane

Grahic Jump Location
Fig. 6

Strain–stress curves obtained from tensile tests

Grahic Jump Location
Fig. 7

SEM fractographs of (a) pure Inconel 718 and (b) Inconel 718 with 0.25 wt. % GNP addition

Grahic Jump Location
Fig. 8

SEM micrographs showing GNPs attached to the fracture surface aligned (a) perpendicular to and (b) parallel to tensile direction and (c) EDS spectrum of GNPs, with 0.25 wt. % GNPs addition




Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In