Deformation of Porous, Nanostructured Silver at Room Temperature and 150 °C

Abstract

Porous, nanostructured silver samples were produced using a direct-write method where a nanoparticle aerosol consisting of particles with a mean size of approximately 5 nm were accelerated to speeds of approximately 1000 m/sec and impacted onto a translating substrate [1]. The impacting particles have sufficient energy to stick to the substrate, allowing patterned thick films to be directly written from the aerosol without a mask. Unlike other low temperature processing routes for achieving patterned films, no organics are added that can interfere with postdeposition processing. Typical films are 5-100 µm thick, up to several centimeters long, and have an as-deposited relative densities as high as 70% of bulk Ag. Compression tests were carried out in steps at room temperature and at 150°C under constant displacement rates. Local strain and densification were measured by optical profilometry between each compression step. The results can be used as a starting point to better understand the mechanisms that govern plasticity, creep, and sintering in nanostructured, porous silver at low processing temperatures.