Direct laser metal deposition (DLMD) additive manufacturing (AM) of Inconel 718 superalloy: Elemental, microstructural and physical properties evaluation

Mahmoud Moradi, Zeynab Pourmand, Arman Hasani, Mojtaba Karami Moghadam, Amir Hosein Sakhaei, Mahmood Shafiee, Jonathan Lawrence

    Research output: Contribution to journalArticlepeer-review

    14 Citations (Scopus)
    57 Downloads (Pure)

    Abstract

    In this study, Direct Laser Metal Deposition (DLMD) technique is adopted for the additive manufacturing (AM) of Inconel 718 Superalloy. A 1 kW fiber laser with a coaxial nozzle head is used. The effects of scanning speed (2.5 and 5 mm/s) as well as powder feed rate (17.94 and 28.52 g/min) on the process were investigated. Characteristics of the 3D printed wall specimens such as the geometrical dimensions (width and height), microstructure observations, and the microhardness were obtained. To study the stability of the 3D manufactured walls, the height stability was considered for the investigation. Optical microscopy (OM), field emission electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), and mapping analysis were performed to derive the microstructural features of the additively manufactured parts (AMP). Vickers microhardness test is used to evaluate the hardness distributions of AMP. Catchment concept of the powder in DLMD process is used for explaining different trends of the process. Results indicated that, by decreasing the scanning speed, the width and height of the deposited layer increase. The average width of AMP directly depends on scanning speed and the powder feed rate. Scanning speed has a reverse effect on the height stability; that is, the lower the scanning speed, the larger the stability. Microstructural results showed that because of the solidification process, the alloying elements will be accumulated in the grain boundaries. The non-uniform cooling rate and non-steady solidification rates of molten area in additive manufacturing process, the microhardness values of the AMP following a fluctuated trend.

    Original languageEnglish
    Article number169018
    Number of pages16
    JournalOptik
    Volume259
    Early online date31 Mar 2022
    DOIs
    Publication statusPublished - 28 Jun 2022

    Bibliographical note

    © 2021, Elsevier. Licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/
    Copyright © and Moral Rights are retained by the author(s) and/ or other copyright owners. A copy can be downloaded for personal non-commercial research or study, without prior permission or charge. This item cannot be reproduced or quoted extensively from without first obtaining permission in writing from the copyright holder(s). The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the copyright holders.

    This document is the author’s post-print version, incorporating any revisions agreed during the peer-review process. Some differences between the published version and this version may remain and you are advised to consult the published version if you wish to cite from it.

    Keywords

    • Additive manufacturing (AM)
    • Dimensional stability
    • Direct laser metal deposition (DLMD)
    • Inconel 718 superalloy
    • Microstructure

    ASJC Scopus subject areas

    • Electronic, Optical and Magnetic Materials
    • Atomic and Molecular Physics, and Optics
    • Electrical and Electronic Engineering

    Fingerprint

    Dive into the research topics of 'Direct laser metal deposition (DLMD) additive manufacturing (AM) of Inconel 718 superalloy: Elemental, microstructural and physical properties evaluation'. Together they form a unique fingerprint.

    Cite this