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Title: Does selective shell printing advance binder jetting additive manufacturing?
Study examines binder deposition methods (bulk vs. selective printing) and sintering atmospheres (vacuum vs. H2) on binder jetted 316 L stainless steel components. The density of the H2-sintered specimens was found to be lower (up to 5%) compared to the vacuum-sintered parts with the final density of 99.7%. Grain size analysis indicated smaller grains in the H2-sintered parts (∼26 μm) compared to vacuum-sintered condition (∼33 μm) in the bound area which could be attributed to the presence of residual pores that impeded grain growth. The H2-sintered specimens exhibited an elongation of 25% and an ultimate tensile strength (UTS) of 460 MPa, whereas the vacuum-sintered parts displayed an elongation of 70% and a UTS of 550 MPa. Fractography analysis using microscopy and micro-computed tomography revealed ductile fracture in the vacuum-sintered samples, while the H2-sintered parts exhibited a combination of brittle and ductile fracture due to remnant pores in the microstructure.  more » « less
Award ID(s):
2050916
PAR ID:
10508354
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Powder Technology
Volume:
441
Issue:
C
ISSN:
0032-5910
Page Range / eLocation ID:
119812
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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