Abstract

Aluminum alloys are candidate materials for weight critical applications because of their excellent strength and stiffness to weight ratio. However, defects such as voids decrease the strength and fatigue life of these alloys, which can limit the application of Selective Laser Melting. In this study, the average volume fraction, average size, and size distribution of pores in Al10-Si-1Mg samples built using Selective Laser Melting have been characterized. Synchrotron high energy X-rays were used to perform computed tomography on volumes of order one cubic millimeter with a resolution of approximately 1.5 μm. Substantial variations in the pore size distributions were found as a function of process conditions. Even under conditions that ensured that all locations were melted at least once, a significant number density was found of pores above 5 μm in diameter.

References

1.
Dinda
,
G. P.
,
Song
,
L.
, and
Mazumder
,
J.
, “
Fabrication of Ti-6Al-4V Scaffolds by Direct Metal Deposition
,”
Metallurgical Mater. Trans. A
, Vol.
39
, No.
12
,
2008
, pp.
2914
2922
. https://doi.org/10.1007/s11661-008-9634-y
2.
Heinl
,
P.
,
Müller
,
L.
,
Körner
,
C.
,
Singer
,
R. F.
, and
Müller
,
F. A.
, “
Cellular Ti–6Al–4V Structures With Interconnected Macro Porosity for Bone Implants Fabricated by Selective Electron Beam Melting
,”
Acta Biomaterialia
, Vol.
4
, No.
5
,
2008
, pp.
1536
1544
. https://doi.org/10.1016/j.actbio.2008.03.013
3.
Edwards
,
P.
,
O'Conner
,
A.
, and
Ramulu
,
M.
, “
Electron Beam Additive Manufacturing of Titanium Components: Properties and performance
,”
J. Manufact. Sci. Eng.
, Vol.
135
, No.
6
,
2013
, p. 061016. https://doi.org/10.1115/1.4025773
4.
Kruth
,
J. P.
,
Leu
,
M. C.
, and
Nakagawa
,
T.
, “
Progress in Additive Manufacturing and Rapid Prototyping
,”
CIRP Annals-Manufacturing Tech.
, Vol.
47
, No.
2
,
1998
, pp.
525
540
. https://doi.org/10.1016/S0007-8506(07)63240-5
5.
Sun
,
J.
,
Yang
,
Y.
, and
Wang
,
D.
, “
Parametric Optimization of Selective Laser Melting for Forming Ti6Al4V Samples by Taguchi Method
,”
Opt. Laser Tech.
, Vol.
49
,
2013
, pp.
118
124
. https://doi.org/10.1016/j.optlastec.2012.12.002
6.
Jia
,
Q.
and
Gu
,
D.
, “
Selective Laser Melting Additive Manufactured Inconel 718 Superalloy Parts: High-Temperature Oxidation Property and Its Mechanisms
,”
Opt. Laser Tech.
, Vol.
62
,
2014
, pp.
161
171
. https://doi.org/10.1016/j.optlastec.2014.03.008
7.
Yadroitsev
,
I.
,
Thivillon
,
L.
,
Bertrand
,
P.
, and
Smurov
,
I.
, “
Strategy of Manufacturing Components With Designed Internal Structure by Selective Laser Melting of Metallic Powder
,”
Appl. Surf. Sci.
, Vol.
254
, No.
4
,
2007
, pp.
980
983
. https://doi.org/10.1016/j.apsusc.2007.08.046
8.
Attar
,
H.
,
Calin
,
M.
,
Zhang
,
L. C.
,
Scudino
,
S.
, and
Eckert
,
J.
, “
Manufacture by Selective Laser Melting and Mechanical Behavior of Commercially Pure Titanium
,”
Mater. Sci. Eng.
, Vol.
593
,
2014
, pp.
170
177
. https://doi.org/10.1016/j.msea.2013.11.038
9.
Lohner
,
A.
, “
Laser Sintering Ushers in New Route to PM Parts
,”
MPR
,
1997
, pp.
24
30
.
10.
Kanagarajah
,
P.
,
Brenne
,
F.
,
Niendorf
,
T.
, and
Maier
,
H. J.
, “
Inconel 939 Processed by Selective Laser Melting: Effect of Microstructure and Temperature on the Mechanical Properties Under Static and Cyclic Loading
,”
Mater. Sci. Eng.
, Vol.
588
,
2013
, pp.
188
195
. https://doi.org/10.1016/j.msea.2013.09.025
11.
Kobryn
,
P. A.
, and
Semiatin
,
S. L.
, “
The Laser Additive Manufacture of Ti-6Al-4V
,”
JOM
, Vol.
53
, No.
9
,
2001
, pp.
40
42
. https://doi.org/10.1007/s11837-001-0068-x
12.
Read
,
N.
,
Wang
,
W.
,
Essa
,
K.
, and
Attallah
,
M. M.
, “
Selective Laser Melting of AlSi10Mg Alloy: Process Optimisation and Mechanical Properties Development
,”
Mater. Design
, Vol.
65
,
2015
, pp.
417
424
. https://doi.org/10.1016/j.matdes.2014.09.044
13.
Hydro, “
Primary Foundry Alloys: Technical Data Sheet AlSi10Mg
http://www.hydro.com/upload/Documents/Products/AlSi10Mga.pdf (Accessed Nov 27, 2015).
14.
Vojtech
,
D.
,
Serak
,
J.
, and
Ekrt
,
O.
, “
Improving the Casting Properties of High-Strength Aluminium Alloys
,”
Materiali Tehnologije
, Vol.
38
,
2004
, pp.
99
102
.
15.
Vilaro
,
T.
,
Abed
,
S.
, and
Knapp
,
W.
, “
Direct Manufacturing of Technical Parts Using Selective Laser Melting: Example of Automotive Application
,”
Proceedings of the 12th European Forum on Rapid Prototyping
,
2008
.
16.
Kempen
,
K.
,
Thijs
,
L.
,
Van Humbeeck
,
J.
, and
Kruth
,
J. P.
, “
Mechanical Properties of AlSi10Mg Produced by Selective Laser Melting
,”
Physics Procedia
, Vol.
39
,
2012
, pp.
439
446
. https://doi.org/10.1016/j.phpro.2012.10.059
17.
Shamsaei
,
N.
,
Yadollahi
,
A.
,
Bian
,
L.
, and
Thompson
,
S. M.
, “
An Overview of Direct Laser Deposition for Additive Manufacturing; Part II: Mechanical Behavior, Process Parameter Optimization and Control
,”
Additive Manufact.
, Vol.
8
,
2015
, pp.
12
35
. https://doi.org/10.1016/j.addma.2015.07.002
18.
Tammas-Williams
,
S.
,
Zhao
,
H.
,
Léonard
,
F.
,
Derguti
,
F.
,
Todd
,
I.
, and
Prangnell
,
P. B.
, “
XCT Analysis of the Influence of Melt Strategies on Defect Population in Ti–6Al–4V Components Manufactured by Selective Electron Beam Melting
,”
Mat. Characterization
, Vol.
102
,
2015
, pp.
47
61
. https://doi.org/10.1016/j.matchar.2015.02.008
19.
Morgan
,
R. H.
,
Papworth
,
A. J.
,
Sutcliffe
,
C.
,
Fox
,
P.
, and
O'Neill
,
W.
, “
High Density Net Shape Components by Direct Laser Re-Melting of Single-Phase Powders
,”
J. Mater. Sci.
, Vol.
37
, No.
15
,
2002
, pp.
3093
3100
. https://doi.org/10.1023/A:1016185606642
20.
Karlsson
,
J.
,
Snis
,
A.
,
Engqvist
,
H.
, and
Lausmaa
,
J.
, “
Characterization and Comparison of Materials Produced by Electron Beam Melting (EBM) of Two Different Ti–6Al–4V Powder Fractions
,”
J. Mater. Process. Technol.
, Vol.
213
, No.
12
,
2013
, pp.
2109
2118
. https://doi.org/10.1016/j.jmatprotec.2013.06.010
21.
Carroll
,
B. E.
,
Palmer
,
T. A.
, and
Beese
,
A. M.
, “
Anisotropic Tensile Behavior of Ti–6Al–4V Components Fabricated With Directed Energy Deposition Additive Manufacturing.
,”
Acta Materialia
, Vol.
87
,
2015
, pp.
309
320
. https://doi.org/10.1016/j.actamat.2014.12.054
22.
Gong
,
H.
,
Rafi
,
K.
,
Gu
,
H.
,
Starr
,
T.
, and
Stucker
,
B.
, “
Analysis of Defect Generation in Ti–6Al–4V Parts Made Using Powder Bed Fusion Additive Manufacturing Processes
,”
Additive Manufact.
, Vol.
1
,
2014
, pp.
87
98
.
23.
Zhou
,
X.
,
Wang
,
D.
,
Liu
,
X.
,
Zhang
,
D.
,
Qu
,
S.
,
Ma
,
J.
,
London
,
G.
,
Shen
,
Z.
, and
Liu
,
W.
, “
3D-Imaging of Selective Laser Melting Defects in a Co–Cr–Mo Alloy by Synchrotron Radiation Micro-CT
,”
Acta Materialia
, Vol.
98
,
2015
, pp.
1
16
. https://doi.org/10.1016/j.actamat.2015.07.014
24.
Tang
,
M.
, and
Pistorius
,
P. C.
, “
Oxides, Porosity and Fatigue Performance of AlSi10Mg Parts Produced by Selective Laser Melting
,” Int. J. Fatigue,
2016
(in press).
25.
Williams
,
J. J.
,
Flom
,
Z.
,
Amell
,
A. A.
,
Chawla
,
N.
,
Xiao
,
X.
, and
De Carlo
,
F.
, “
Damage Evolution in SiC Particle Reinforced Al Alloy Matrix Composites by X-ray Synchrotron Tomography
,”
Acta Materialia
, Vol.
58
, No.
18
,
2010
, pp.
6194
6205
. https://doi.org/10.1016/j.actamat.2010.07.039
26.
Singh
,
S. S.
,
Williams
,
J. J.
,
Hruby
,
P.
,
Xiao
,
X.
,
De Carlo
,
F.
, and
Chawla
,
N.
, “
In Situ Experimental Techniques to Study the Mechanical Behavior of Materials Using X-ray Synchrotron Tomography
,”
Integrating Mater. Manufact. Innovation
, Vol.
3
, No.
1
,
2014
, pp.
1
14
.
27.
Gürsoy
,
D.
,
De Carlo
,
F.
,
Xiao
,
X.
, and
Jacobsen
,
C.
, “
TomoPy: A Framework for the Analysis of Synchrotron Tomographic Data
,”
J. Synchrotron Radiat.
, Vol.
21
, No.
5
,
2014
, pp.
1188
1193
. https://doi.org/10.1107/S1600577514013939
29.
Magnusen
,
P. E.
,
Bucci
,
R. J.
,
Hinkle
,
A. J.
,
Brockenbrough
,
J. R.
, and
Konish
,
H. J.
, “
Analysis and Prediction of Microstructural Effects on Long-Term Fatigue Performance of an Aluminum Aerospace Alloy
,”
Int. J. Fatigue
, Vol.
19
, No.
93
,
1997
, pp.
275
283
. https://doi.org/10.1016/S0142-1123(97)00044-3
30.
Wadell
,
H.
, “
Volume, Shape, and Roundness of Quartz Particles
,”
J. Geology
,
1935
, Vol.
43
, No.
3
, pp.
250
280
. https://doi.org/10.1086/624298
31.
Ziółkowski
,
G.
,
Chlebus
,
E.
,
Szymczyk
,
P.
, and
Kurzac
,
J.
, “
Application of X-ray CT Method for Discontinuity and Porosity Detection in 316L Stainless Steel Parts Produced With SLM Technology
,”
Archives Civil Mech. Eng.
, Vol.
14
, No.
4
,
2014
, pp.
608
614
. https://doi.org/10.1016/j.acme.2014.02.003
32.
Tang
,
M.
,
Pistorius
,
P. C.
, and
Beuth
,
J.
, “
Geometric Model to Predict Porosity of Part Produced in Powder Bed System
,”
Mater. Sci. Technol.
,
2015
, pp.
129
135
.
33.
Beuth
,
J.
,
Fox
,
J.
,
Gockel
,
J.
,
Montgomery
,
C.
,
Yang
,
R.
,
Qiao
,
H.
,
Soylemez
,
E.
,
Reeseewatt
,
P.
,
Anvari
,
A.
,
Narra
,
S.
, and
Klingbeil
,
N.
, “
Process Mapping for Qualification Across Multiple Direct Metal Additive Manufacturing Processes
,”
Proceedings of SFF Symposium
,
Austin, TX
,
2013
, pp.
12
14
.
This content is only available via PDF.
You do not currently have access to this content.