The additive manufacturing (AM) process is unique in that it can facilitate anisotropy because of the layer-by-layer deposition technique intrinsic to this process. In order to develop a component for a desired application, it is necessary to understand the mechanics that facilitate this material behavior. This study investigates how build orientation affects the mechanical performance of as-built direct metal laser sintered (DMLS) stainless steel (SS) GP1 (also referred to as 17-4PH) through strain-controlled monotonic tension and completely reversed low-cycle fatigue (LCF) testing. The anisotropic behavior of DMLS SS GP1 is assessed for samples built along the horizontal plane. Fracture surfaces were found to exhibit ductile responses that were consistent with the σε curves. Constitutive models (i.e., Ramberg–Osgood, Hahn) based upon linear elasticity and nonlinear plasticity are presented and used to simulate the monotonic discontinuous stress–strain yielding response of this material, which are found to be in agreement with the experimental data. A collection of low-cycle fatigue tests reveals initial strain hardening to stabilization, followed by softening to fracture. Tensile and fatigue material constants determined from experimental findings are also presented in this study. Plasticity effects on the life of varying build orientations are explored.

References

References
1.
Kok
,
Y.
,
Tan
,
X. P.
,
Wang
,
P.
,
Nai
,
M. L. S.
,
Loh
,
N. H.
,
Liu
,
E.
, and
Tor
,
S. B.
,
2018
, “
Anisotropy and Heterogeneity of Microstructure and Mechanical Properties in Metal Additive Manufacturing: A Critical Review
,”
Mater. Des.
,
139
, pp.
565
586
.
2.
EOS GmbH- Electro Optical Systems
,
2009
, “
EOS StainlessSteel GP1 for EOSINT M 270 Material Data Sheet
,” pp.
1
5
.
3.
Cheruvathur
,
S.
,
Lass
,
E. A.
, and
Campbell
,
C. E.
,
2015
, “
Additive Manufacturing of 17-4PH Stainless Steel: Post-Processing Heat Treatment to Achieve Uniform Reproducible Microstructure
,”
J. Mater.
,
68
(
3
), pp.
930
942
.
4.
Facchini
,
L.
,
Vicente
,
N.
,
Lonardelli
,
I.
,
Magalini
,
E.
,
Robotti
,
P.
, and
Molinari
,
A.
,
2010
, “
Metastable Austenite in 17-4 Precipitation-Hardening Stainless Steel Produced by Selective Laser Melting
,”
Adv. Eng. Mater.
,
12
(
3
), pp.
184
188
.
5.
Luecke
,
W. E.
, and
Slotwinski
,
J. A.
,
2014
, “
Mechanical Properties of Austenitic Stainless Steel Made by Additive Manufacturing
,”
J. Res. Natl. Inst. Stand. Technol.
,
119
, pp.
398
418
.
6.
Yadollahi
,
A.
,
Shamsaei
,
N.
,
Thompson
,
S. M.
,
Elwany
,
A.
,
Bian
,
L.
, and
Mahmoudi
,
M.
,
2015
, “
Fatigue Behavior of Selective Laser Melted 17-4PH Stainless Steel
,”
Proceedings of the 26th International Solid Freeform Fabrication Symposium
,
Austin, TX
,
Aug. 10–12
, pp.
721
731
.
7.
Mower
,
T. M.
, and
Long
,
M. J.
,
2016
, “
Mechanical Behavior of Additive Manufactured, Powder-Bed Laser-Fused Materials
,”
Mater. Sci. Eng. A
,
651
, pp.
198
213
.
8.
Siddiqui
,
S. F.
,
O'Nora
,
N.
,
Fasoro
,
A.
, and
Gordon
,
A. P.
,
2017
, “
Modeling the Influence of Build Orientation on the Monontonic and Cyclic Response of Additively Manufactured Stainless Steel GP1/17-4PH
,”
Proceedings of the ASME 2017 International Mechanical Engineering Conference and Exposition
,
Tampa, FL
,
Nov. 3–9
, IMECE2017-71561.
9.
Yadollahi
,
A.
,
Shamsaei
,
N.
,
Thompson
,
S. M.
,
Elwany
,
A.
, and
Bian
,
L.
,
2017
, “
Effects of Building Orientation and Heat Treatment on Fatigue Behavior of Selective Laser Melted 17-4 PH Stainless Steel
,”
Int. J. Fatigue
,
94
, pp.
218
235
.
10.
Everhart
,
W.
,
Sawyer
,
E.
,
Neidt
,
T.
,
Dinardo
,
J.
, and
Brown
,
B.
,
2016
, “
The Effect of Surface Finish on Tensile Behavior of Additively Manufactured Tensile Bars
,”
J. Mater. Sci.
,
51
(
8
), pp.
3836
3845
.
11.
Siddiqui
,
S. F.
,
Fasoro
,
A. A.
, and
Gordon
,
A. P.
2018
, “
Torsional Response of Additively Manufactured Steel Under Monotonic and Cyclic Conditions
,”
ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition
,
Oslo, Norway
,
June 11–15
, pp.
1
7
.
12.
Stoffregen
,
H. A.
,
Butterweck
,
K.
, and
Abele
,
E.
2014
, “
Fatigue Analysis in Selective Laser Melting: Review and Investigation of Thin-Walled Actuator Housings
,”
25th Solid Freeform Fabrication Symposium
,
Austin, TX,
pp.
635
650
.
13.
ASTM
,
2015
, “
Standard Test Methods for Tension Testing of Metallic Materials
,”
ASTM International
,
West Conshohocken
,
PA
, Standard No.
ASTM E8 / E8M-15a
14.
Siddiqui
,
S.F.
2018
, “
Characterization of Anisotropic Mechanical Performance of As-Built Additively Manufactured Metals
,” Ph.D. dissertation,
University of Central Florida
, pp.
1
266
.
15.
Kelley
,
P. F.
Jr.
,
2016
, “
Fatigue Behavior of Direct Metal Laser Sintered (DMLS) Inconel 718
,” Master's thesis,
Tufts University
,
Medford
,
MA
.
16.
Siddiqui
,
S. F.
,
Fasoro
,
A. A.
, and
Gordon
,
A. P.
,
2017
, “
Chapter 14: Selective Laser Melting (SLM) of Ni-based Superalloys – A Mechanics of Materials Review
,”
Additive Manufacturing Handbook: Product Development for the Defense Industry
,
A. B.
Badiru
,
V. V.
Valencia
, and
D.
Liu
, eds.,
Taylor & Francis/CRC Press
,
Boca Raton, FL
, pp.
225
249
.
17.
EOS M-Solutions, 06/201
3
, “
Laser Sintering System EOSINT M 280 for the Production of Tooling Inserts, Prototype Parts and End Products Directly in Metal
,”
Krailing/Munich
,
Germany
.
18.
AK Steel Corporation
,
2007
,
Product Data Sheet 17-4PH Stainless Steel
,
West Chester
,
OH
.
19.
ASTM
,
2013
, “
Standard Test Method for Creep-Fatigue Testing
,”
ASTM International
,
West Conshohocken
,
PA
, Standard No.
ASTM E2714-13
20.
Murr
,
L. E.
,
Martinez
,
E.
,
Hernandez
,
J.
,
Collins
,
S.
,
Amato
,
K. N.
,
Gaytan
,
S. M.
, and
Shindo
,
P. W.
,
2012
, “
Microstructures and Properties of 17-4PH Stainless Steel Fabricated by Selective Laser Melting
,”
J. Mater. Res. Technol.
,
1
(
3
), pp.
167
177
.
21.
Tan
,
X.
,
Kok
,
Y.
,
Toh
,
W. Q.
,
Tan
,
Y. J.
,
Descoins
,
M.
,
Mangelinck
,
D.
, and
Chua
,
C. K.
,
2016
, “
Revealing Martensitic Transformation and α/β Interface Evolution in Electron Beam Melting Three-Dimensional-Printed Ti-6Al-4V
,”
Sci. Rep.
,
6
,
26039
.
22.
Mahmoudi
,
M.
,
Elwany
,
A.
,
Yadollahi
,
A.
,
Thompson
,
S. M.
,
Bian
,
L.
, and
Shamsaei
,
N.
,
2017
, “
Mechanical Properties and Microstructural Characterization of Selective Laser Melted 17-4PH Stainless Steel
,”
Rapid Prototyp. J.
,
23
(
2
), pp.
280
294
.
23.
Hahn
,
G. T.
,
1962
, “
A Model for Yielding With Special Reference to the Yield-Point Phenomena of Iron and Related bcc Metals
,”
Acta Metall.
,
10
(
8
), pp.
727
738
.
24.
Shioya
,
T.
, and
Shioiri
,
J.
,
1976
, “
Elastic-Plastic Analysis of the Yield Process in Mild Steel
,”
J. Mech. Phys. Solids
,
24
(
4
), pp.
187
204
.
25.
Kraft
,
S. M.
, and
Gordon
,
A. P.
,
2011
, “
Characterization of the Tensile Behavior of a Metallic Fiber Woven Structure
,”
Textile Res. J.
,
81
(
12
), pp.
1249
1272
.
26.
Bouchenot
,
T.
,
Gordon
,
A. P.
,
Shinde
,
S.
, and
Gravett
,
P.
,
2014
, “
Approach for Stabilized Peak/Valley Stress Modeling of Non-Isothermal Fatigue of a DS Ni-Base Superalloy
,”
Mater. Perform. Charact.
,
3
(
2
), pp.
16
43
.
You do not currently have access to this content.