Development of Aluminium Wire as an UHV Compatible Demountable Seal

A B S T R A C T Aluminium and Copper wire-seals were fabricated and characterized as ultra-high vacuum (UHV) demountable wire-seals for large sized non-circular openings. A vacuum system used to measure integrated helium leak rate over the whole circumference of the wire-seal and the wire compression at particular compression force is described. The results show that the leak rate of the order of 1 × 10 – 10 mbar l/s can be achieved by applying the force per unit length of 258 kN/m to aluminium wire-seal with compression of 25 %, while to obtain the same order of leak rate in copper wire-seal, the force per unit length is 415 kN/m at the compression of 44 %.