PLUGGING STRUCTURE FOR VESSELS

摘要

A plugging body (6) for vessels which is made from a functionally gradient material composed of nonconductive and conductive components connected together so as to have a continuous or stepwise concentration gradient in the axial direction of a vessel to thereby make the material itself nonconductive on one side and conductive on the other side, plugs side tubes (3) joined to a luminous tube (2), and has a hole (10) into which an electrode core (7) is tightly shrinkage fitted. In this body, at least part of the surface of the electrode core (7) positioned in the hole (10) is coated with a thin film of a metal having a high melting point so as to prevent the craking of the plugging body (6) in the course of sintering the body (6).