A Study on Mechanical Behaviors for Various Cooling Rate and Working Temperature of 5-Element Alloys Nanowires with Amorphous Structures by Molecular Dynamics Simulation
| Autor: | Chi-Ting Wu, 吳其庭 |
|---|---|
| Rok vydání: | 2017 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 105 The study analyzes solidification behavior of silver – gold – palladium – copper – nickel, silver – gold – iron – copper – nickel, silver – gold – titanium – copper – nickel nanowires after melting at high temperature then rapid cooling. Additionally, mechanical properties and deformation behavior of alloy nanowires are also investigated with simple tension test after rapid cooling by using molecular dynamics simulation. Results show that three types of nanowires cooled by lower cooling rate will exhibit higher level of crystallization. In the same cooling rate, the different crystal structure and crystal system of component Element has lower the crystallization. After using cooling alloy relaxation balance, it will show higher crystallization. Difference between atomic radii is larger, so the crystallization is lower. In amorphous material, mechanism of deformation is different from single crystal material. The single crystal material use dislocation by slipping. Amorphous material which occur atoms displacement is caused by forming and disappearing of the free volume, and becoming regular arrangement of shear band which lead to stress yielding. Because of Nano Bridge, the silver – gold – palladium – copper – nickel alloy nanowire in the cooling rate 1×1013K/s has the best ductility. the silver – gold – palladium – copper – nickel alloy nanowire in the cooling rate 1×1012K/s has the higest crystallization and yield strength. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|