DESIGN, FABRICATION, AND MECHANICAL CHARACTERIZATION OF 3D HOLLOW CERAMIC NANO-ARCHITECTURES

Add to your list(s) Download to your calendar using vCal

• Prof. Dongchan Jang, KAIST
• Friday 23 November 2018, 14:30-15:30
• Evetts meeting room, Department of Materials Science & Metallurgy.

If you have a question about this talk, please contact an426.

Abstract

Density-strength tradeoff appears to be an inherent limitation for most materials and therefore design of cell topology that mitigates strength decrease with density reduction has been a long-lasting engineering pursue for porous materials. Continuum-mechanics-based analyses on mechanical responses of the conventional porous materials with bending-dominated structures often give the density-strength scaling law following the power-law relationship with exponent of 1.5 or higher, which consequentially determines the upper bound of the specific strength for a material to reach. In this work, we present a new design criterion capable of significantly abating strength degradation in lightweight materials, by successfully combining size-induced strengthening effect in nanomaterials with architectural design of cellular porous materials. Hollow-tube-based 3D ceramic nano-architectures satisfying such criterion were fabricated in large area using Proximity field nano-Patterning (PnP) and atomic layer deposition (ALD). Experimental data from micro-pillar compression confirmed that the strengths of these nano-architectural materials scale with relative densities with power-law exponent of 0.93, hardly observable value in the conventional bending-dominated porous materials. Our discovery of new density-strength scaling law in the nano-architectured materials will contribute to creating new lightweight structural materials attaining unprecedented specific strengths overcoming the conventional limit.

This talk is part of the Microstructural Kinetics Group - Department of Materials Science & Metallurgy series.

This talk is included in these lists:

• Evetts meeting room, Department of Materials Science & Metallurgy
• Microstructural Kinetics Group - Department of Materials Science & Metallurgy

Note that ex-directory lists are not shown.