Max Planck Partner Group “Extreme mechanics of 3D nano-architected oxides”

Electron beam irradiation-based deformation processes in 3D nano-architected oxides at extreme strain rates and temperatures

This project aims to investigate the combined mechanical responses of 3D nano-architected oxides under the influence of electron-beam irradiation, strain rate, and temperature. The intrinsic brittleness of oxides can be alleviated through variations in temperature, material size, and the application of electron-beam irradiation [1,2]. In this study, the combined effects on the mechanical response of 3D nano-architected oxides will be systematically examined using an in-situ SEM micromechanical testing system equipped with a piezo-actuator and precise temperature control systems. This project seeks to deepen the understanding of oxide deformation induced by electron-beam irradiation and its dependencies on size, strain rate, and temperature.

For material fabrication, we will employ a combination of localized electrodeposition, atomic layer deposition, and selective etching. Localized electrodeposition enables the fabrication of metallic microarchitectures with resolutions on the order of hundreds of nanometers [3]. Subsequently, an oxide layer, tens of nanometers thick, will be deposited onto the metallic microarchitectures via atomic layer deposition. Finally, selective etching of the metal core will produce the nano-architected oxide structures.

Deformation behavior and corresponding mechanical properties will be studied through in-situ SEM micromechanical tests. Electron-beam parameters will be calibrated based on an electron-matter interaction model. Deformation behavior will be evaluated under high temperatures and under electron-beam irradiation to confirm whether the same deformation mechanisms are at play. Additional investigations over a wide range of strain rates and at low temperatures (−150 °C) will explore the characteristics of viscoplastic deformation induced by electron-beam irradiation, distinguishing these effects from those observed under high-temperature conditions above the glass transition temperature.