Investigation of a new material and sealing geometry for aluminum-based components in ultra-high vacuum applications

ConFlat® sealing components are of great significance in ultra-high vacuum systems. The vacuum-tight connection is achieved by pressing the sealing surface of a knife-edge geometry into an inserted soft metal flat gasket. In this context, aluminum-based vacuum components have several advantages compared to steel-based components, such as lower magnetic permeability or lower material outgassing. A major disadvantage of aluminum is its lower strength, which is why soft-annealed copper gaskets are required. This paper presents a new aluminum-based knife-edge geometry that can also be used for standard copper gaskets. In addition, the wear behavior could be reduced by 90 % and the long-term thermal stability significantly increased up to 200 °C.