FIM observation of point defect clusters in ion-implanted tungsten surfaces
| Autor: | N Igata, S Sato |
|---|---|
| Rok vydání: | 1993 |
| Předmět: |
Materials science
Annealing (metallurgy) business.industry Mechanical Engineering Analytical chemistry chemistry.chemical_element Bioengineering General Chemistry Tungsten Crystallographic defect Charged particle Ion Optics chemistry Mechanics of Materials Vacancy defect Radiation damage General Materials Science Irradiation Electrical and Electronic Engineering business |
| Zdroj: | Nanotechnology. 4:213-217 |
| ISSN: | 1361-6528 0957-4484 |
| DOI: | 10.1088/0957-4484/4/4/006 |
| Popis: | The objective of this study is to observe the point defects in ion-implanted tungsten surfaces using a field-ion microscope (FIM) and to analyse radiation damage processes from an atomistic standpoint. The materials used for these measurements were tungsten wire, 0.1 mm in diameter, with purities of 99.95% and 99.999%. The specimens were irradiated with various kinds of ion having energies of around 100-400 keV. The total dose was approximately= 0.01-10 DPA (displacement per atom) and the irradiation temperature was 293 K. The FlM observation was performed on (112), (121) and (217) planes for every atomic layer within the mean projected range (i.e. the mean path including forward and backward motion). The size distribution was taken as an average through the mean projected range. The maximum vacancy cluster size observed after various kinds of ion irradiation was 1.5 mm. The total number of vacancies was proportional to the square root of the total dose of irradiation at 293 K. The total number of vacancies at a given level of average concentration of injected charged particles was proportional to the square root of the maximum primary knock-on energy. Defect concentration was a function of specimen purity, high-purity specimens having defect concentrations less than those of low-purity ones. The annealing process was also investigated. |
| Databáze: | OpenAIRE |
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