金丝垫圈的放气率低,可重复使用,又耐高温烘烤,密封可靠,但用黄金太昂贵,这就限制了它的广泛应用。用保险丝作垫圈,则价廉易作,延展性良好,使用方便。若能经受200℃以上的长时间烘烤而不漏气,则用它作为超高真空系统中的密封垫圈就有其广泛使用的意义了。为此,我们在不锈钢真空系统中,用保险丝(98％铅,2％锡)作法兰密封垫圈,进行超高真空获得的实验。在200～240℃下烘烤8小时,在充分冷却之后,系统极限压强达到了3.6×10~(-10)托。一、密封机制金属垫圈密封属于非限制压缩密封。当金属垫圈在两法兰之间被压缩时,法兰与垫圈的接触界面处可能会形成微小的、不规则的孔道而构成漏隙。这些漏隙的形状由表面接触时的 Gold gaskets low outgassing, reusable, but also baking high temperature, reliable sealing, but the gold is too expensive, which limits its wide range of applications. Fuse for gaskets, the cheap easy to make, good ductility, easy to use. If you can withstand prolonged baking over 200 ℃ without leakage, then use it as a seal in the ultra-high vacuum system has its significance. To do this, we experimented with ultra-high vacuum in a stainless steel vacuum system using a fuse (98% lead, 2% tin) as a flange gasket. Baking at 200 ~ 240 ℃ for 8 hours, after cooling sufficiently, the system reaches a pressure limit of 3.6 × 10 ~ (-10) Torr. First, the sealing mechanism Metal gasket seal is a non-limiting compression seal. When the metal gasket is compressed between the two flanges, the flange and the gasket contact interface may form tiny, irregular channels to form a leak. The shape of these leaks when contacted by the surface