Next Article in Journal
Effect of Oxygen Nonstoichiometry on Electrical Conductivity and Thermopower of Gd0.2Sr0.8FeO3−δ Ferrite Samples
Next Article in Special Issue
Effect of Scanning and Support Strategies on Relative Density of SLM-ed H13 Steel in Relation to Specimen Size
Previous Article in Journal
In-Situ and Ex-Situ Characterization of Femtosecond Laser-Induced Ablation on As2S3 Chalcogenide Glasses and Advanced Grating Structures Fabrication
Previous Article in Special Issue
The Effect of Selective Laser Melting Process Parameters on the Microstructure and Mechanical Properties of Al6061 and AlSi10Mg Alloys
Open AccessArticle

Impacts of Defocusing Amount and Molten Pool Boundaries on Mechanical Properties and Microstructure of Selective Laser Melted AlSi10Mg

1
Department of Materials Science and Engineering Shenzhen Key Laboratory for Additive Manufacturing of High-Performance Materials, South University of Science and Technology of China, Shenzhen 518055, China
2
Key Laboratory of Artificial Micro- and Nano-Materials of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan 430072, China
3
Centre for Additive Manufacture, School of Engineering, RMIT University, Melbourne, VIC 3000, Australia
*
Author to whom correspondence should be addressed.
Materials 2019, 12(1), 73; https://doi.org/10.3390/ma12010073
Received: 23 November 2018 / Revised: 10 December 2018 / Accepted: 18 December 2018 / Published: 26 December 2018
(This article belongs to the Special Issue Additive Manufacturing: Alloy Design and Process Innovations)
The influences of processing parameters such as volumetric energy density (ε) and, particularly, defocusing amount (DA) on densification, microstructure, tensile property, and hardness of the as-printed dense AlSi10Mg alloy by selective laser melting (SLM) were studied systematically. The molten pool boundaries (MPBs) were found overwhelmingly at regular and complex spatial topological structures affected by DA value to exist in two forms, while the “layer–layer” MPB overlay mutually and the “track–track” MPBs intersect to form acute angles with each other. The microstructure of MPBs exhibits a coarse grain zone near the MPBs and the characteristics of segregation of nonmetallic elements (O, Si) where the crack easily happened. The DA value (−2 to 2 mm) affected both the density and the tensile mechanical properties. High tensile strength (456 ± 14 MPa) and good tensile ductility (9.5 ± 1.4%) were achieved in the as-printed condition corresponding to DA = 0.5 mm. The tensile fracture surface features were analyzed and correlated to the influence of the DA values. View Full-Text
Keywords: aluminum alloys; selective laser melting (SLM); mechanical properties aluminum alloys; selective laser melting (SLM); mechanical properties
Show Figures

Graphical abstract

MDPI and ACS Style

Zhou, S.; Su, Y.; Gu, R.; Wang, Z.; Zhou, Y.; Ma, Q.; Yan, M. Impacts of Defocusing Amount and Molten Pool Boundaries on Mechanical Properties and Microstructure of Selective Laser Melted AlSi10Mg. Materials 2019, 12, 73.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop