超流動ヘリウム中で使用可能の, ステンレススチール中空Oリング

抄録

For low temperature vacuum seals, O-rings of soft metals such as indium, lead, and gold have been used extensively. Besides these, stainless steel hollow O-rings are also usable for the same purpose. No vacuum seal of this type, however, has been reported so far, which is proved to be leak-tight in liquid helium.
We have found that commercially available silver-plated stainless steel hollow O-rings and Teflon-coated ones provide reliable superleak-tight seals and they can be used repeatedly.