Microscopic evolution of pre-damaged and undamaged tungsten exposed to low-energy and high-flux helium ions

作者：Yang, Qi; Liu, Dongping^*; Fan, Hongyu; Li, Xin; Niu, Jinhai; Wang, Younian

来源：Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms , 2014, 325: 73-78.

DOI：10.1016/j.nimb.2014.02.011

• Conductive atomic force microscopy
• Irradiation
• He bubbles

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.

• 出版日期2014-4-15
• 单位大连理工大学; 大连民族大学; 厦门大学