Segregation of 316L stainless steel powder during spreading in selective laser melting based additive manufacturing

316L stainless steel parts were manufactured via selective laser melting . This work stu- dies the effects of powder characteristics such as particle size and particle shape composition on the density. It shows that the powder with a broad size distribution and using spherical fine powder can lead to an increase in the density of the loose powder and thus the densification of the laser melted powder. The aerosol powder forms parts of lower oxygen content well, and the density can reach to 90%.

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Characterization of laser spatter and condensate generated during the selective laser melting of 304L stainless steel powder

Additive Manufacturing ◽

10.1016/j.addma.2019.100904 ◽

2020 ◽

Vol 31 ◽

pp. 100904 ◽

Cited By ~ 1

Author(s):

Austin T. Sutton ◽

Caitlin S. Kriewall ◽

Ming C. Leu ◽

Joseph W. Newkirk ◽

Ben Brown

Keyword(s):

Stainless Steel ◽

Selective Laser Melting ◽

Steel Powder ◽

Stainless Steel Powder ◽

304L Stainless Steel ◽

Laser Melting

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Water Atomized 17-4 PH Stainless Steel Powder as a Cheaper Alternative Powder Feedstock for Selective Laser Melting

Materials Science Forum ◽

10.4028/www.scientific.net/msf.941.698 ◽

2018 ◽

Vol 941 ◽

pp. 698-703 ◽

Cited By ~ 2

Author(s):

Milad Ghayoor ◽

Sunil B. Badwe ◽

Harish Irrinki ◽

Sundar V. Atre ◽

Somayeh Pasebani

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Stainless Steel ◽

Selective Laser Melting ◽

Steel Powder ◽

Melting Process ◽

Stainless Steel Powder ◽

Laser Melting ◽

Austenitic Phase ◽

Process Gas

Water atomized and gas atomized 17-4 PH stainless steel powder were used as feedstock in selective laser melting process. Gas atomized powder revealed single martensitic phase after printing and heat treatment. As-printed water atomized powder contained dual martensitic and austenitic phase. The H900 heat treatment cycle was not effective in enhancing mechanical properties of the water atomized powder after laser melting. However, after solutionizing at 1315 oC and aging at 482oC fully martensitic structure was observed with yield strength of 1000 MPa and ultimate tensile strength of 1261 MPa which are comparable to those of gas atomized, 1254 MPa and 1300 MPa, respectively. Improved mechanical properties in water atomized powder was found to be related to presence of finer martensite. Our results imply that water atomized powder is a promising cheaper feedstock alternative to gas atomized powder.

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Effect of Powder Feedstock on Microstructure and Mechanical Properties of the 316L Stainless Steel Fabricated by Selective Laser Melting

Metals ◽

10.3390/met8090729 ◽

2018 ◽

Vol 8 (9) ◽

pp. 729 ◽

Cited By ~ 12

Author(s):

Wei Chen ◽

Guangfu Yin ◽

Zai Feng ◽

Xiaoming Liao

Keyword(s):

Mechanical Properties ◽

Stainless Steel ◽

Additive Manufacturing ◽

Selective Laser Melting ◽

316L Stainless Steel ◽

Hierarchical Structures ◽

Fine Powder ◽

Tensile Tests ◽

Laser Melting ◽

Powder Feedstock

Additive manufacturing by selective laser melting (SLM) was used to investigate the effect of powder feedstock on 316L stainless steel properties include microstructure, relative density, microhardness and mechanical properties. Gas atomized SS316L powders of three different particle size distribution were used in this study. Microstructural investigations were done by scanning electron microscopy (SEM). Tensile tests were performed at room temperatures. Microstructure characterization revealed the presence of hierarchical structures consisting of solidified melt pools, columnar grains and multiform shaped sub-grains. The results showed that the SLM sample from the fine powder obtained the highest mechanical properties with ultimate tensile strength (UTS) of 611.9 ± 9.4 MPa and yield strength (YS) of 519.1 ± 5.9 MPa, and an attendant elongation (EL) of 14.6 ± 1.9%, and a maximum of 97.92 ± 0.13% and a high microhardness 291 ± 6 HV0.1. It has been verified that the fine powder (~16 μm) could be used in additive manufacturing with proper printing parameters.

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