About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
30 Years of Nanoindentation with the Oliver-Pharr Method and Beyond
|
Presentation Title |
Mechanics of Non-equilibrium Thin Films |
Author(s) |
Graham LW Cross |
On-Site Speaker (Planned) |
Graham LW Cross |
Abstract Scope |
Compression of a supported thin film by a precision-aligned, flat micro-punch at extremely high aspect ratios approximates uniaxial strain up to moderate strain while simulating nanoimprint forming processes at high strain. For the first case, we show how this “Layer Compression Test” allows direct, assumption-free measurement of intrinsic stress-vs-strain for soft matter materials down to the 10’s nm scale. Combined with synchrotron-based scanned X-ray microscopy, we present measurements of isothermal polymeric plastic flow in confined to extruded conditions exhibiting homogeneous, defect-free densification that violates the notion of thermal ageing reversal postulated as a general outcome of large shear in disordered matter. Our results contrast with rejuvenation reported for bulk metallic glass macro-scale specimens subject to triaxial compression, agreeing instead with scattered observations of compactification during eg. calendaring in the polymer mechanics literature. We further report structure-property relations of advanced 2D nanocomposites formed by additive manufacturing techniques measured by the technique. |
Proceedings Inclusion? |
Planned: |
Keywords |
Mechanical Properties, Polymers, Nanotechnology |