In the present study, laser engineered net shaping technology was successfully utilised to fabricate 316L stainless steel bulk specimens using unidirectional scanning path and weaving scanning path. Influence of scanning path and post-heat treatment on microstructural and mechanical properties of the as-deposited builds has been investigated. The results show that scanning paths have a significant impact on the grain morphology evolution. Consequently, the as-made samples by different scanning strategies show a great difference in the mechanical properties. Furthermore, the experimental results also demonstrate that post-heat treatment is an essential step in further optimising microstructure and improving mechanical properties.
PoncheR., KerbratO., MognolP. and HascoetJ.-Y.: ‘A novel methodology of design for additive manufacturing applied to additive laser manufacturing process’, Robot. Cim-int. Manuf., 2014, 30, (4), 389–398. doi: 10.1016/j.rcim.2013.12.001
2.
GockelJ., FoxJ., BeuthJ. and HafleyR.: ‘Integrated melt pool and microstructure control for Ti–6Al–4V thin wall additive manufacturing’, Mater. Sci. Technol., 2015, 31, (8), 912–916. doi: 10.1179/1743284714Y.0000000704
3.
ManvatkarV., DeA. and DebRoyT.: ‘Spatial variation of melt pool geometry, peak temperature and solidification parameters during laser assisted additive manufacturing process’, Mater. Sci. Technol., 2015, 31, (8), 924–930. doi: 10.1179/1743284714Y.0000000701
4.
BaufeldB., BiestO. v. d., GaultR. and RidgwayK.: ‘Manufacturing Ti-6Al-4V components by shaped metal deposition: microstructure and mechanical properties’, IOP Conf. Ser.: Mater. Sci. Eng., 2011, 26, 012001. doi: 10.1088/1757-899X/26/1/012001
5.
XiongY., SmugereskyJ. E., AjdelsztajnL. and SchoenungJ. M.: ‘Fabrication of WC–Co cermets by laser engineered net shaping’, Mater. Sci. Eng. A, 2008, 493, (1–2), 261–266. doi: 10.1016/j.msea.2007.05.125
6.
FergusonJ. B., SchultzB. F., MoghadamA. D. and RohatgiP. K.: ‘Semi-empirical model of deposit size and porosity in 420 stainless steel and 4140 steel using laser engineered net shaping’, J. Manuf. Proc., 2015, 19, 163–170. doi: 10.1016/j.jmapro.2015.06.026
7.
LuZ. L., LiD. C., LuB. H., ZhangA. F., ZhuG. X. and PiG.: ‘The prediction of the building precision in the laser engineered net shaping process using advanced networks’, Opt. Laser Eng., 2010, 48, (5), 519–525. doi: 10.1016/j.optlaseng.2010.01.002
8.
EspañaF. A., BallaV. K., BoseS. and BandyopadhyayA.: ‘Design and fabrication of CoCrMo alloy based novel structures for load bearing implants using laser engineered net shaping’, Mater. Sci. Eng. C, 2010, 30, (1), 50–57. doi: 10.1016/j.msec.2009.08.006
9.
QiuC., RaviG. A., DanceC., RansonA., DilworthS. and AttallahM. M.: ‘Fabrication of large Ti–6Al–4V structures by direct laser deposition’, J. Alloy Compd., 2015, 629, 351–361. doi: 10.1016/j.jallcom.2014.12.234
10.
DurejkoT., ZiętalaM., PolkowskiW. and CzujkoT.: ‘Thin wall tubes with Fe3Al/SS316L graded structure obtained by using laser engineered net shaping technology’, Mater. Design, 2014, 63, 766–774. doi: 10.1016/j.matdes.2014.07.011
11.
El CheikhH., CourantB., BranchuS., HuangX., HascoëtJ.-Y. and GuillénR.: ‘Direct laser fabrication process with coaxial powder projection of 316L steel. Geometrical characteristics and microstructure characterization of wall structures’, Opt. Laser Eng., 2012, 50, (12), 1779–1784. doi: 10.1016/j.optlaseng.2012.07.002
12.
RaviG. A., HaoX. J., WainN., WuX. and AttallahM. M.: ‘Direct laser fabrication of three dimensional components using SC420 stainless steel’, Mater. Design, 2013, 47, 731–736. doi: 10.1016/j.matdes.2012.12.062
13.
ZhangK., WangS., LiuW. and ShangX.: ‘Characterization of stainless steel parts by laser metal deposition shaping’, Mater. Design, 2014, 55, 104–119. doi: 10.1016/j.matdes.2013.09.006
14.
ZhaoX., ChenJ., LinX. and HuangW.: ‘Study on microstructure and mechanical properties of laser rapid forming Inconel 718’, Mater. Sci. Eng. A, 2008, 478, (1–2), 119–124. doi: 10.1016/j.msea.2007.05.079
15.
WangZ., GuanK., GaoM., LiX., ChenX. and ZengX.: ‘The microstructure and mechanical properties of deposited-IN718 by selective laser melting’, J. Alloys Compd., 2012, 513, 518–523. doi: 10.1016/j.jallcom.2011.10.107
16.
BonthaS., KlingbeilN. W., KobrynP. A. and FraserH. L.: ‘Effects of process variables and size-scale on solidification microstructure in beam-based fabrication of bulky 3D structures’, Mater. Sci. Eng. A, 2009, 513–514, 311–318. doi: 10.1016/j.msea.2009.02.019
17.
QiuC., RaviG. A. and AttallahM. M.: ‘Microstructural control during direct laser deposition of a β-titanium alloy’, Mater. Design, 2015, 81, 21–30. doi: 10.1016/j.matdes.2015.05.031
18.
SunG., TongZ., FangX., LiuX., NiZ. and ZhangW.: ‘Effect of scanning speeds on microstructure and wear behavior of laser-processed NiCr–Cr3C2–MoS2–CeO2 on 38CrMoAl steel’, Opt. Laser Technol., 2016, 77, 80–90. doi: 10.1016/j.optlastec.2015.08.008
19.
ChenJ. L., LiJ., SongR., BaiL. L., ShaoJ. Z. and QuC. C.: ‘Effect of the scanning speed on microstructural evolution and wear behaviors of laser cladding NiCrBSi composite coatings’, Opt. Laser Technol., 2015, 72, 86–99. doi: 10.1016/j.optlastec.2015.03.015
20.
WangT., ZhuY. Y., ZhangS. Q., TangH. B. and WangH. M.: ‘Grain morphology evolution behavior of titanium alloy components during laser melting deposition additive manufacturing’, J. Alloys Compd., 2015, 632, 505–513. doi: 10.1016/j.jallcom.2015.01.256
21.
MaM., WangZ., WangD. and ZengX.: ‘Control of shape and performance for direct laser fabrication of precision large-scale metal parts with 316L Stainless Steel’, Opt. Laser Technol., 2013, 45, 209–216. doi: 10.1016/j.optlastec.2012.07.002
22.
DaiK. and ShawL.: ‘Distortion minimization of laser-processed components through control of laser scanning patterns’, Rapid Prototyp. J., 2002, 8, (5), 270–276(277). doi: 10.1108/13552540210451732
23.
PengL., TaipingY., ShengL., DongshengL., QianwuH., WeihaoX. and XiaoyanZ.: ‘Direct laser fabrication of nickel alloy samples’, Int. J. Mach. Tool Manu., 2005, 45, (11), 1288–1294. doi: 10.1016/j.ijmachtools.2005.01.014
24.
HeB., LiD., ZhangA., GeJ., YangX. and HuX.: ‘Influence of scanning pattern on the edge collapse of solid parts in laser metal direct forming’, Opt. Laser Technol., 2013, 48, 171–177. doi: 10.1016/j.optlastec.2012.10.006
25.
LiuF., LinX., HuangC., SongM., YangG., ChenJ. and HuangW.: ‘The effect of laser scanning path on microstructures and mechanical properties of laser solid formed nickel-base superalloy Inconel 718’, J. Alloys Compd., 2011, 509, (13), 4505–4509. doi: 10.1016/j.jallcom.2010.11.176
26.
TaberneroI., LamikizA., MartínezS., UkarE. and FiguerasJ.: ‘Evaluation of the mechanical properties of Inconel 718 components built by laser cladding’, Int. J. Mach. Tool Manu., 2011, 51, (6), 465–470. doi: 10.1016/j.ijmachtools.2011.02.003
27.
LuY., WuS., GanY., HuangT., YangC., JunjieL. and LinJ.: ‘Study on the microstructure, mechanical property and residual stress of SLM Inconel-718 alloy manufactured by differing island scanning strategy’, Opt. Laser Technol., 2015, 75, 197–206. doi: 10.1016/j.optlastec.2015.07.009
28.
HuntJ. D.: ‘Steady state columnar and equiaxed growth of dendrites and eutectic’, Mater. Sci. Eng., 1984, 65, 75–83. doi: 10.1016/0025-5416(84)90201-5
29.
GriffithM., SchliengerM., HarwellL., OliverM., BaldwinM., EnszM., EssienM., BrooksJ., RobinoC. and SmugereskyJ. E.: ‘Understanding thermal behavior in the LENS process’, Mater. Design, 1999, 20, (2), 107–113. doi: 10.1016/S0261-3069(99)00016-3
30.
YadollahiA., ShamsaeiN., ThompsonS. M. and SeelyD. W.: ‘Effects of process time interval and heat treatment on the mechanical and microstructural properties of direct laser deposited 316L stainless steel’, Mater. Sci. Eng. A, 2015, 644, 171–183. doi: 10.1016/j.msea.2015.07.056
31.
ShifengW., ShuaiL., QingsongW., YanC., ShengZ. and YushengS.: ‘Effect of molten pool boundaries on the mechanical properties of selective laser melting parts’, J. Mater. Process Technol., 2014, 214, (11), 2660–2667. doi: 10.1016/j.jmatprotec.2014.06.002
