Study on the Effect of Laser Parameters on the SEY of Aluminum Alloy

The laser treated surface method is a novel way to mitigate electron cloud in high-energy and high-intensity particle accelerators. Aluminum alloy is a common and important material used in the vacuum system construction of particle accelerators. The influences of laser parameters, such as scanning speed and average laser power on the secondary electron yield (SEY) and surface morphology of laser processed aluminum alloy samples, were studied and explored in this paper. The as-received laser processed aluminum alloy surfaces with SEY less than 1 were obtained. The surface composition and topography were tested by the X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and laser scanning confocal microscopy (LSCM). The XPS results revealed that the surface of as-received laser processed aluminum alloys consists of aluminum oxide layer and intermetallic aluminum. The LSCM and SEM results show that the selection of appropriate laser parameters and hatched patterns was ascertained by the surface topography of the sample to obtain low-SEY surface.