Title
Comparing Spherical and Irregularly Shaped Powders in Laser Powder Bed Fusion of Nb47Ti Alloy
Date Issued
01 September 2021
Access level
metadata only access
Resource Type
journal article
Author(s)
Guzmán J.
de Moura Nobre R.
Rodrigues Júnior D.L.
de Morais W.A.
Nunes E.R.
Bayerlein D.L.
Falcão R.B.
Oliveira H.R.
Chastinet V.L.
Landgraf F.J.G.
Institute for Technological Research (IPT)
Publisher(s)
Springer
Abstract
Literature reports that irregularly shaped powder has lower flowability and apparent density than spherical shaped powder, factors that hinder its use in additive manufacturing, although its cost is potentially lower. In this study, four samples of Nb47Ti alloy manufactured by laser powder bed fusion from plasma atomized (PA) and hydride–dehydride (HDH) powders with different scanning strategies and interstitial element content were compared. Laser power levels of 200 W and 300 W were investigated. To keep a constant powder mass under the laser beam, the processing table displacement for samples from the HDH powder was twice larger than the 30 µm used for samples from the PA powder procedure, due to the lower apparent density of the HDH powder. It was possible to achieve porosity levels below 1% with both powders. However, the power of 200 W generated 13% of porosity in the HDH samples. A similar microstructure formed by melt pools and cellular dendritic structure in a β phase matrix of body-centered cubic (BCC) structure was obtained in all samples. Furthermore, the low interstitial element content of samples from PA powder resulted in lower microhardness when compared to the higher interstitial element content of samples from HDH powder.
Start page
6557
End page
6567
Volume
30
Issue
9
Language
English
OCDE Knowledge area
Ingeniería de materiales Ingeniería mecánica
Scopus EID
2-s2.0-85107508694
Source
Journal of Materials Engineering and Performance
ISSN of the container
10599495
Sponsor(s)
The authors would like to express their gratitude to the São Paulo Research Foundation (FAPESP) (process number 2016/50199-6), the Brazilian Metallurgy and Mining Company (CBMM), the Disabled Child Care Association (AACD), and the Brazilian Agency for Industrial Research and Innovation (EMBRAPII) for their financial support. R.B. Falcão (Grant No. 2017/20926-6) and Edwin Sallica-Leva (Grant No. 2017/20877-5) gratefully acknowledge FAPESP for providing postdoctoral fellowships. F.J.G. Landgraf acknowledges CNPq support to project 307631/2018-4. Jhoan Guzmán acknowledges Emerson Titonello for his collaboration during the experiments. Thanks must also be given to S.D. Brandi and G.F.B. Lenz e Silva for their collaboration in the hardness and hydrostatic density tests.
Sources of information: Directorio de Producción Científica Scopus