Surface Near Helium Damage in Materials Studied with a High Throughput Implantation Method

Helium damage in materials is of interest to the nuclear fusion, fission and spallation community. Helium generation in bulk either generate by nuclear reactions or by direct implantation can cause embrittlements and swelling while Helium implantation in surface near areas can lead to blistering, fuzz formation and spalling. All phenomena listed are based on the accumulation of Helium into nanosized bubbles as a function of temperature and external stress states driven by the insolubility of Helium in the material. Studying these phenomena traditionally requires ion beam accelerators and large samples. In this work we introduced nanobeam ion beam implantation methods which enable rapid multi dose ion beam implantation in surface near regions to enable basic scientific studies in single crystal and polycrystal materials such as Cu, Si, W, V. The combination of Helium ion beam implantation using the Helium Ion Beam Microscope, Atomic Force Microscopy, Nanoindentation and Transmission Electron Microscope allows to bring insight into the formation of blisters, the linking up of Helium bubbles and the associated deformation and cracking mechanism.<br/>On Tungsten, we were able to confirm previously posed hypothesis in tungsten blistering and how helium bubbles link up to form surface near blisters all the way to spalling phenomena. The work on silicon shows the interplay between Silicon amorphisation and bubble formation leading to cracking in the material. The work on Vandium and Cu shows the change in microcompression and plasticity behaviour as a function of helium dose and how bubbles rearrange themselfs under these curcumstances. Simple analytical approaches describing the observed phenomena are presented in this work.