| dc.description.abstract | This project idea is proposed in order to develop the understanding of the mechanisms responsible for Nano-crystal phase formation when metallic glasses (amorphous) is exposed under the high energy ion irradiation and is quantified the resulting effects on the material behavior. The objectives of this project are to: (1) quantify the response of metallic glasses to ion irradiation, specifically, damage cascade formation and subsequent structural evolutions along ion tracks, (2) identify the mechanisms responsible for ion irradiation-induced Nano-crystallization, specifically, the paths of crystal nucleation and growth, and effects of energy deposition rate and subsequent energy dissipation rate on crystal formation, (3) quantify the resulting crystal phases, densities and distribution under different ion irradiation conditions and identify the governing factors to reach controllable crystal formation, and (4) measure the hardness elastic modulus and ductility of the metallic glasses containing Nano-crystals created by ion irradiation, and quantify shear band interactions with crystal of different sizes, shapes and matrix distribution.
It is expected that this study will contribute to new fundamental understanding of mechanisms responsible for the creation of Nano-crystals in metallic glasses by ion irradiation, and the role of the altered structure in the modification of the materials mechanical response. It will impact fundamental understanding in several materials science subfields. In the field of ion-solid interactions, phase transitions from amorphous to crystalline in metallic materials are poorly understood. This study will contribute to a more complete understanding of the structural evolution occurring over different time scales involving damage cascade creation, thermal spike formation, and structural relaxation. The roles of excess free volume and thermal energy deposition on the mechanisms responsible for Nano-crystal phase formation will be identified. In the field of Nano-mechanical behavior of materials, this study will identify the roles of Nano-crystals on the mechanical response of metallic glasses. It will further contribute to our understanding of shear band nucleation and propagation, and deflection and attenuation by Nano-crystals of different mechanical strengths and interaction cross sections. | en |
