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Indexed by:期刊论文

Date of Publication:2014-04-15

Journal:NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS

Included Journals:SCIE、EI、Scopus

Volume:325

Page Number:73-78

ISSN No.:0168-583X

Key Words:Conductive atomic force microscopy; Irradiation; He bubbles

Abstract:High-energy (260 keV) He+ pre-damaged and undamaged polycrystalline tungsten samples were irradiated with low-energy (220 eV) and high-flux (similar to 10(21) ions/m(2) s) He+ at a sample temperature of 873 K to a fluence of 1.0 x 10(25) ions/m(2). Microscopic evolution of these samples was carried out using non-destructive conductive atomic force microscopy and a nanohardness test. Analysis indicates that a large number of nanometer-sized protuberances of irradiated tungsten samples results from over-high internal pressure of nanometer-sized helium bubbles. Ordered and nanostructured helium bubbles with the same diameter and average spacing can be formed due to the self-trapping and self-organizing of helium atoms in the tungsten materials. In the case of pre-damaged, low-energy He+ irradiation results in a random distribution of nanostructured helium bubbles, indicating that high-energy He+ implantation results in serious irradiation damage of tungsten materials, acting as nuclei for helium bubbles. (C) 2014 Elsevier B.V. All rights reserved.