Precipitation of implanted krypton in aluminium

• Published in: Journal of nuclear materials Vol. 135; no. 2; pp. 274 - 276
• Main Authors: Birtcher, R.C., Jäger, W.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.10.1985; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Ion radiation effects; Materials science; Metals, semimetals and alloys; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Other interactions of matter with particles and radiation; Physical radiation effects, radiation damage; Physics; Specific materials; Structure of solids and liquids; crystallography; Ion implantation; FCC crystals; Gas cavity; Dislocation structure; Vacancy cluster; Precipitate; Dislocation loop; Krypton; Solid state; Bubble; Precipitation; Krypton ion; Microstructure; Internal pressure
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/0022-3115(85)90088-1

The use of energetic noble gas atoms for ion beam mixing studies or the modification of materials necessitates an understanding of the effects produced by the retained gas atoms. A systematic study of the microstructural evolution in Al after 65 keV Kr + implantation (dose range 2 × 10 16 Kr + m −2 ≤ φ ≤ 6 × 10 20 Kr + m −2, at ambient temperature was performed using transmission electron microscopy (TEM) and Rutherford backscattering (RBS). At low doses (≲2 × 10 18 Kr + m −2) isolated dislocation loops and the evolution of a dislocation network is observed. For φ 10 19 Kr + m −2 the microstructure is dominated by a high density of small cavities. Additional reflections in the electron diffraction pattern indicate that the cavities (bubbles) contain solid fcc Kr epitaxially aligned with the fcc Al. A typical internal pressure of about 22 kbar can be estimated for bubbles 1.7 nm in diameter and 16 kbar for 2.8 nm bubbles. The average bubble size increases with φ, and for φ $ ̆ 2 × 10 20 Kr +m −2 an increasing Kr fraction is in a liquid or gas-like phase.