TY  - JOUR
A1  - Hertz-Eichenrode, David
A1  - Talebinezhad, H.
A1  - Shmatok, A.
A1  - Fischer, R. D.
A1  - Bremen, Sebastian
A1  - Reichert, Walter
T1  - 4D porosity evolution in additively manufactured 316L stainless steel through in-situ tensile testing and X-ray computed tomography
T2  - Experimental Mechanics
N2  - Background:  Many aspects of ductile failure through microvoid coalescence remain elusive due to the challenging spatial and temporal scales it operates on. Experimentally resolving all aspects of the process remains a significant goal of researchers. Much of the current understanding has been derived from post-mortem metallography, leaving key aspects of its evolution undocumented.
Objective:  This work builds on efforts using X-ray computed tomography (XCT) characterize voids and their evolution under loading.
Methods:  It employs in-situ XCT tensile testing on 316L Stainless Steel samples that were constructed by laser powder bed fusion that contain tailored, pre-existing voids with a spatial scale relevant to the growth and evolution stages of microvoid coalescence. Pre-existing voids extended the observation window for monitoring void growth and interaction under loading. They also enhanced fiducial correlation of voids during deformation.
Results:  Void populations were found to increase under loading as their deformed dimensions rendered them detectable by the XCT algorithm. Neighboring voids underwent interconnection events by a cleavage process when stress concentrations between them exceeded the macroscopic yield stress. Pores that did not undergo interconnection events were found to revert to their initial size and population after unloading. Finally, the porosity structure before failure was correlated to features on the fracture surface with high fidelity.
Conclusions:  This unique combination of in-situ XCT tensile testing on samples with tailored void structure enabled new visualization and quantification of void evolution under load as well as strong correlation to the observed stress–strain behavior and post-mortem fracture characteristics.
KW  - In-situ tensile testing
KW  - X-ray computed tomography
KW  - Additive manufacturing
KW  - Microvoid coalescence
KW  - 4D porosity analysis
Y1  - 2025
UR  - https://opus.bibliothek.fh-aachen.de/opus4/frontdoor/index/index/docId/12754
SN  - 1741-2765
PB  - Springer
CY  - Boston, Mass.
ER  -