Formation of AlSi10Mg surfaces via selective laser melting: scanning electron microscopy and Raman spectroscopy study

The paper studies the atomization of Al-based alloy AlSi12 in gas jet. Air was used as a spraying gas. The size and shape of powder particles were studied by using scanning electron microscopy and optical granulomorphometer. The obtained powder was used in selective laser melting.

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The Effect of Building Direction on Microstructure and Microhardness during Selective Laser Melting of Ti6Al4V Titanium Alloy

Journal of Materials Engineering and Performance ◽

10.1007/s11665-021-06039-x ◽

2021 ◽

Author(s):

D. Palmeri ◽

G. Buffa ◽

G. Pollara ◽

L. Fratini

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Titanium Alloy ◽

Additive Manufacturing ◽

Selective Laser Melting ◽

Laser Melting ◽

Ti6al4v Titanium Alloy ◽

Mechanical Performances ◽

Scanning Electron

AbstractDuring the last few years, additive manufacturing has been more and more extensively used in several industries, especially in the aerospace and medical device fields, to produce Ti6Al4V titanium alloy parts. During the Selective Laser Melting (SLM) process, the heterogeneity of finished product is strictly connected to the scan strategies and the building direction. An optimal managing of the latter parameters allows to better control and defines the final mechanical and metallurgical properties of parts. Acting on the building direction it is also possible to optimize the critical support structure. In particular, more support structures are needed for the sample at 0°, while very low support are required for the sample at 90°. To study the effects of build direction on microstructure heterogeneity evolution and mechanical performances of selective laser melted Ti6Al4V parts, two build direction samples (0°, 90°) were manufactured and analyzed using optical metallographic microscope (OM) and scanning electron microscopy (SEM). Isometric microstructure reconstruction and microhardness tests were carried out in order to analyze the specimens. The obtained results indicate that the build direction has to be considered a key geometrical parameter affecting the overall quality of the obtained products.

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Microstructural Characterization of the Anisotropy and Cyclic Deformation Behavior of Selective Laser Melted AlSi10Mg Structures

Metals ◽

10.3390/met8100825 ◽

2018 ◽

Vol 8 (10) ◽

pp. 825 ◽

Cited By ~ 9

Author(s):

Mustafa Awd ◽

Felix Stern ◽

Alexander Kampmann ◽

Daniel Kotzem ◽

Jochen Tenkamp ◽

...

Keyword(s):

Electron Microscopy ◽

Mechanical Properties ◽

Scanning Electron Microscopy ◽

Selective Laser Melting ◽

Microstructural Characterization ◽

Fatigue Tests ◽

Laser Melting ◽

Structural Anisotropy ◽

Scanning Electron

The laser-based fusion of metallic powder allows construction of components with arbitrary complexity. In selective laser melting, the rapid cooling of melt pools in the direction of the component building causes significant anisotropy of the microstructure and properties. The objective of this work is to investigate the influence of build anisotropy on the microstructure and mechanical properties in selective laser melted AlSi10Mg. The alloy is comprehensively used in the automotive industry and has been one of the most frequently investigated Al alloys in additive manufacturing. Using specimens produced in three different building orientations with respect to the build platform, the anisotropy of the microstructure and defects will be investigated using scanning electron microscopy and microcomputed tomography. The analysis showed a seven-times higher pore density for the 90°-specimen compared to the 0°-specimen. The scanning electron microscopy revealed the influence of the direction of the cooling gradient on the constitution of the eutectic phase. Mechanical properties are produced in quasi-static and fatigue tests of variable and constant loading amplitudes. Specimens of 0° showed 8% higher tensile strength compared to 90°-specimens, while fracture strain was reduced almost 30% for the 45°-specimen. The correlation between structural anisotropy and mechanical properties illustrates the influence of the building orientation during selective laser melting on foreseen fields of application.

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Characterization of alkali treated flax fibres by means of FT Raman spectroscopy and environmental scanning electron microscopy

Spectrochimica Acta Part A Molecular and Biomolecular Spectroscopy ◽

10.1016/s1386-1425(01)00697-7 ◽

2002 ◽

Vol 58 (10) ◽

pp. 2271-2279 ◽

Cited By ~ 117

Author(s):

A Jähn ◽

M.W Schröder ◽

M Füting ◽

K Schenzel ◽

W Diepenbrock

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Raman Spectroscopy ◽

Environmental Scanning Electron Microscopy ◽

Environmental Scanning ◽

Flax Fibres ◽

Ft Raman Spectroscopy ◽

Scanning Electron ◽

Ft Raman

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Improving the reactivity of phenylacetylene macrocycles toward topochemical polymerization by side chains modification

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.10.167 ◽

2014 ◽

Vol 10 ◽

pp. 1613-1619 ◽

Cited By ~ 4

Author(s):

Simon Rondeau-Gagné ◽

Jules Roméo Néabo ◽

Maxime Daigle ◽

Katy Cantin ◽

Jean-François Morin

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Raman Spectroscopy ◽

Self Assembly ◽

Significant Enhancement ◽

Side Chains ◽

X Ray Diffraction ◽

X Ray ◽

Topochemical Polymerization ◽

Scanning Electron

The synthesis and self-assembly of two new phenylacetylene macrocycle (PAM) organogelators were performed. Polar 2-hydroxyethoxy side chains were incorporated in the inner part of the macrocycles to modify the assembly mode in the gel state. With this modification, it was possible to increase the reactivity of the macrocycles in the xerogel state to form polydiacetylenes (PDAs), leading to a significant enhancement of the polymerization yields. The organogels and the PDAs were characterized using Raman spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM).

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