| Abstract Scope |
Nanoporous gold (np-Au) is a material with sponge-like structure, composed of continuously connected ligament and pore in nanoscale. Due to low density and high surface area-to-volume ratio, np-Au is applied as catalyst, actuator, and sensor. However, in np-Au, brittleness remains as an issue to be overcome. Brittleness appears as pore generates stress concentration and ligaments are sequentially failed right after crack nucleation. Grain boundary is, also, another cause of stress concentration, so early crack nucleation is observed at grain boundary.
Here, we focus on microstructure of np-Au for the enhancement of mechanical properties. Sputtering and rolling process are used to design grain boundary characteristics and grain morphology of Au-Ag precursor alloy. Free corrosion is performed on Au-Ag precursor alloys to fabricate np-Au with diverse ligament/pore. Mechanical properties are measured with multi-scale mechanical test, and influence of microstructure on the mechanical behavior is investigated with SEM, EBSD, and TEM. |