| 摘要 |
<p>PURPOSE:To improve the life-span of a direct heating type cathode structure and its functional characteristics, by using a specific clad material to constitute each filament, on whose surface is fixed a metallic base plate coated with an electron radiating material. CONSTITUTION:The filaments 8 are extended between their corresponding heads of supports 2 and springs 7 of a cathode structure. A metallic base plate 9 is fixed on substantial center of each filament 8. The surface of each metallic base plate 9 is coated with an electron radiating material. As each filament of the structure is used a clad material which is made of a heat resistant metal, such as Mo or W, coated with an Ni-base heat resistant alloy. For example, the clad material may be made by using Mo11 as a core material, cladding an Ni-W alloy 12 over the core material and forming the clad material into a symmetrical comfiguration with respect to its vertical and transverse directions.</p> |
