| 摘要 |
<p>PURPOSE:To improve the life of a cathode by baking powder of Co or Co-Ni on the part to be coated with an oxide of a substrte melt of alloy the main component of which is Ni and containing Zr as a reducing agent to prevent the oxide from peeling off. CONSTITUTION:Powder of Co or Co-Ni 4 is baked on the part of a substrate metal 1 to be coated with an oxide 3 for emission of electrons, the substrate metal 1 contains Zr as a reducing agent of a directly heated type oxide cathode and is constituted with alloy the main component of which is Ni. It is preferable that the substrate metal 1 contains 0.04-5wt% of Zr, and the Co-Ni powder contains Co in a proportion of not less than 80wt% and Ni in a proportion of not more than 20wt%. The coated amount of the powder of Co or Co-Ni on the substrate metal 1 is preferably 0.1-5mg/cm<2>. The substrate metal is preferably constituted with Ni as the main component, one or more of high melting point metals such as W, Mo, and Re, and Zr as a reducing agent.</p> |
