Harold Barnard







Accelerator for Materials Analysis (masters thesis)

01 Sep 2009


For my masters research I built an accelerator facility to perform ion beam analysis (IBA) on plasma facing materials from fusion reactors. The accelerator was built from a decommissioned hardware and components from a 1.7 megavolt tandem accelerator that were donated to the lab. This accelerator construction and upgrade project was done in collaboration with P.W. Stahle and D.G.Whyte and took about 3 years. The result was a fully functional linear accelerator user facility for materials research with a focus or plasma facing material for fusion reactors.


After completion the accelerator construction, I developed a beamline that produced external ion beams (the beam passes a 7 micron vacuum tight foil into the air) that is used to study large reactor components in air that would otherwise fit in an evacuated target chamber.


Using this accelerator and the external IBA setup, I was able to analyze plasma facing components that were removed from the reactor to study erosion and deposition patterns of materials such tungsten (W) caused by the high temperature plasma inside of fusion devices. I was also able to map out the erosion patterns of boron plasma coatings on the surface of reactor wall materials.