5th International Congress on 3D Materials Science (3DMS 2021): Wednesday Invited
Program Organizers: Dorte Juul Jensen, Technical University of Denmark; Erica Lilleodden, Fraunhofer Insitute for Microstructure of Materials and Systems (IMWS); Scott Barnett, Northwestern University; Keith Knipling, Naval Research Laboratory; Matthew Miller, Cornell University; Akira Taniyama, The Japan Institute of Metals and Materials; Hiroyuki Toda, Kyushu University; Lei Zhang, Chinese Academy of Sciences
Wednesday 11:10 AM
June 30, 2021
Room: Virtual A
Location: Virtual
Session Chair: Lei Zhang, Chinese Academy of Sciences
11:10 AM Invited
Gaining Insights into Complex Dynamics of Coarsening in Bicontinuous Structures: W. Beck Andrews1; Kate Elder2; Markus Ziehmer3; Erica Lilleoddenc,3; Peter W. Voorhees2; Katsuyo Thornton1; 1University of Michigan; 2Northwestern University; 3Helmholtz-Zentrum Geesthacht
Bicontinuous structures form frequently in nature as a result of phase separation. These structures continue to evolve due to the excess surface energy toward structures with larger feature sizes. Currently, there is no theory that predicts the morphology resulting from such evolution. In this presentation, the findings from phase field simulations of coarsening in a variety of systems, ranging from those with bulk diffusion to surface diffusion, as well as different volume fractions and mobilities, are summarized. The morphologies of the structures are characterized via interfacial shape distributions and phase/curvature auto-correlations, and their topologies are also quantified. A comparison to nanoporous gold structure is presented, and implications of particle detachment and reattachment are discussed.
11:40 AM Invited
Analysis of Grain Structure and Voids within Additive Manufactured 316L by Serial Sectioning: David Rowenhorst1; 1Naval Research Laboratory
One advantage of serial-sectioning is the ability to analyze large volumes while maintaining a relatively high resolutions. Additionally, there are multiple imaging modes that can be used for each section surface, allowing for more precise segmentation of features. Here we present a method wherein electron backscattered images are used to resolve pore defects in additively manufactured 316L, while Electron Backscattered Diffraction (EBSD) is used to resolve the grain structure. Due to the high-tilt imaging conditions of the EBSD, the spatial distortions were removed by comparing common features within each of the two datasets and aligning the 3D datasets. This then allowed for co-analysis of the data where we show that small grains are highly correlated with lack of fusion pores within the AM material, indicating that the pores may play a significant role as nucleation sites for new grains during AM processing.