Comprehensive overview of materials, sealing methods and vulnerabilities of UHV systems for particle accelerators

With the development of modern science and technology, the use and modernization of particle accelerators are becoming more relevant and promising. Research and experiments in the field of elementary particle physics are carried out on various types of accelerator equipment. The modernization is based on improving both the characteristics of the entire accelerator and some parameters of its specific unit or even a sub-unit. It is apparent that almost all accelerator components have flanges that are used in different places for their intended purpose. In particular, for connecting waveguides of different diameters, connecting any unit measuring devices, vacuum gauges, or direct closure of the unit. The degree of sealing of the flanges has a strong influence on the beam parameters since the degree of vacuum has a great impact on the working parameters of the beam. Austenitic stainless steel, high-strength aluminum alloys and dispersion-strengthened copper alloys are used as materials for flange connections. These materials have limited parameters in terms of strength characteristics. Repeated assembly and disassembly of such joints leads to subsequent deformation of the flanges. This phenomenon limits the multiple uses of flanges. Thus, the work studied the currently known standard and non-standard models of ultrahigh vacuum flanges, gaskets, and methods of their sealing. As the main purpose of the overview, further research issues to be solved are derived.