Self-organizing Nano-architectured Materials: Mechanical Properties and Advanced Characterization
Program Organizers: Yu-chen Karen Chen-Wiegart, Stony Brook University / Brookhaven National Laboratory; Ian Mccue, Northwestern University; Erica Lilleodden, Fraunhofer Insitute for Microstructure of Materials and Systems (IMWS); Pierre-Antoine Geslin, CNRS / INSA-Lyon; Qing Chen, Hong Kong University of Science & Technology
Tuesday 2:30 PM
March 1, 2022
Room: 260C
Location: Anaheim Convention Center
Session Chair: Erica Lilleodden, Helmholtz-Zentrum hereon; Yu-chen Karen Chen-Wiegart, Stony Brook University / Brookhaven National Laboratory
2:30 PM Invited
Architected Nanocomposites with Exceptional Energy Dissipation: Lorenzo Valdevit1; Jens Bauer1; Marti Sala Casanovas1; 1University of California, Irvine
The concept of combining a metallic and a ceramic phase in a composite material has been employed for decades as a strategy to achieve excellent combinations of high temperature resistance, wear resistance, strength, ductility and energy absorption. Conventional manufacturing approaches rely on dispersing a discontinuous ceramic reinforcement (particles or fibers) in a continuous metallic matrix. While this strategy may be effective under specific service conditions, numerous studies have shown that interpenetrating phase composites (IPCs) with optimized phase topologies can provide far superior combinations of properties. Yet fabricating metal-ceramic IPCs with micro-nanoscale architectures remains a substantial challenge. Here we present a nano-architected IPC consisting of a glassy carbon architected shell interdispersed with an electrodeposited Nickel matrix. The nanoscale ceramic shell approaches its theoretical strength, while the metallic phase provides ductility. The result is a material that can sustain stress plateaus of 2GPa over strains in excess of 60%.
3:00 PM
Mechanical Properties of Two Photon Lithographed Structures Made Using Nanocluster-based Resins: John Kulikowski1; Qi Li1; David Doan1; Wendy Gu1; 1Stanford University
Two photon lithography (TPL) offers a high precision means to create architected materials with arbitrary geometries having the potential to be used as lightweight structural materials. Here, we implement a custom photoresist containing metallic nanoclusters which remain in the printed structures. Further, high temperature pyrolysis of these structures under inert gas is used to produce carbon-metal structures with up to 80% shrinkage compared to the polymeric material. Interestingly, this process produces nano-porous structures. Mechanical properties of both the nano-porous pyrolyzed and as printed polymeric embedded structures are characterized using compression on cylindrical structures. Properties of the polymeric-metal structures are investigated as a function of nanocluster composition. Increases in the volume fraction of metallic nanoclusters leads to improvements in the mechanical properties. Pyrolyzed structure mechanical properties are studied as a function of both nanoporous percentage and pyrolysis parameters. The mechanical properties of porous architected lattices are evaluated.
3:20 PM
Persistence of Crystal Orientations across Sub-micron-scale “Super-grains” in Self-organized Cu-W Nanocomposites: Kelvin Xie1; Digvijay Yadav1; Dexin Zhao1; Arun Devaraj2; Michael Demkowicz1; 1Texas A&M University; 2Pacific Northwest National Lab
We use precession electron diffraction to investigate the crystallographic character of copper (Cu)-tungsten (W) nanocomposites fabricated via physical vapor co-deposition at 400 °C. We observe sub-micron-scale regions, where apparently disconnected Cu and W grains have near-identical crystallographic orientations. This persistence of grain orientations suggests Cu and W grains within these regions are interconnected in 3-D when they first form and may be considered as intercalated, sub-micron-scale “super-grains”. Indeed, atom probe tomography provides direct evidence of 3-D interconnectivity of W domains. Our findings shed light on the structure and self-organization mechanisms of nanocomposites formed by spontaneous phase separation of co-deposited metals.
3:40 PM Break
4:00 PM Invited
Characterization of Particle Impact and Pore Formation in Directed Energy Deposition via In-situ, Highspeed Imaging and Micro X-ray Computed Tomography: Samantha Webster1; Jian Cao1; Newell Moser2; Edward Garboczi2; Sarah Wolff3; Kamel Fezzaa4; Tao Sun5; 1Northwestern University; 2National Institute of Standards and Technology; 3Texas A&M University; 4Argonne National Laboratory; 5University of Virginia
Process defects currently limit the use of additive manufacturing (AM) components in industry due to shorter fatigue life, potential for catastrophic failure, and lower strength. Conditions under which these defects form, and their mechanisms, are starting to be characterized through in-situ, high-speed X-ray imaging of both laser powder bed fusion (LPBF) and directed energy deposition (DED). However, it is evident that particle impact in powder blown DED will illicit very different behavior due to stochastic, violent powder delivery. In this study, highspeed X-ray imaging at the Advanced Photon Source (APS) was utilized in conjunction with a high through-put DED set-up to observe particle impact behavior and types of pore formation in both single track and multi-layer builds. An analytical model adapted from hydrophobic solid particle entrance into a liquid is presented and connected to pore characterization via micro X-ray Computed Tomography (CT) conducted at the National Institute of Standards and Technology.
4:30 PM
3-dimensionally Ordered Interpenetrating Tungsten-silicon Oxycarbide Nanocomposites for High-temperature Applications: Kevin Schmalbach1; Zhao Wang1; R. Lee Penn1; David Poerschke1; Antonia Antoniou2; Andreas Stein1; Nathan Mara1; 1University of Minnesota; 2Georgia Institute of Technology
Metal-ceramic nanocomposites display unique mechanical properties due to synergy between their parent components. We have created an ordered tungsten-silicon oxycarbide nanocomposite intended for use in high temperature applications. Colloidal templates were used to create tungsten inverse opals with approximate ligament thicknesses of 30 nm and window openings of 225 nm. The inverse opals were further infiltrated with preceramic polymer precursor to form amorphous silicon oxycarbide. The resulting structure was characterized with electron microscopy, x-ray diffraction, and spectroscopic techniques to determine the crystalline phases and nanocomposite morphology under different processing conditions. The mechanical properties of the nanocomposite were tested via in situ micropillar compression from 30 to 575 °C, revealing distinct deformation modes at higher temperatures and displaying a 22-fold increase in maximum strength at 30 °C as compared to the tungsten inverse opal alone.
4:50 PM Brief break for prepare for reception
5:00 PM Reception