*In this study, the surrogate pores were designed, generated and investigated with different process parameters in tensile specimens fabricated by laser powder bed fusion (L-PBF) process. The objectives are to demonstrate the feasibility of the pore generation, and to characterize the pores and examine the effect of various process conditions on the pores. The pore-generated specimens were fabricated in an L-PBF system with Ti-6Al-4V (Ti64) powder. Additional single and 5 layers of individual tracks were exposed in the middle portion of the specimen during fabrication to generate the keyhole pores. Then, the pores were observed using X-ray micro CT (XCT), and analyzed qualitatively and quantitatively with respect to the processes. The XCT results showed that pore formation increased with more layers exposed, although individual tracks exhibited variously in the single-layer-exposed specimens. Large quantities of 11-track pores in 5-layers disappear after fracture; whereas,3-track-pore specimens showed increasing volume and consistent pore numbers. Besides, high power and high energy density both tended to generate keyhole pores compared to lower settings. Failure analysis in the representative 5-layer-exposed specimens indicated that pores had a significant effect on the ductility of the specimens with different pore tracks, but were indifferent on tensile strength and Young’s modulus.*


Surrogate Pore Generations in L-Pbf Ti64 and Effects on Mechanical Behavior

Division / Sponsor: 
Manufacturing Engineering Division (MED)

International Manufacturing Science and Engineering Conference - Paper Proceedings: https://asmedigitalcollection.asme.org/MSEC/MSEC2020/volume/84256

JSME 2020 Conference on Leading Edge Manufacturing/Materials and Processing - Paper Proceedings: https://asmedigitalcollection.asme.org/lemp/LEMP2020/volume/83624

MSEC2020 - Virtual Conference, LEMP2020 - Virtual Conference

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