CATHODE FOR CATHODE-RAY TUBE AND MANUFACTURE THEREOF

PROBLEM TO BE SOLVED: To shorten the time required for reduction of an oxide, and to restrain peeling of the oxide from a base metal surface by finishing into a coarse face the surface of a cathode base body provided with the oxide as an electron radiation substance. SOLUTION: A cathode base body 17 consists of a cup-shaped molded nickel alloy, and contains a fine quantity of a reducer such as magnesium or tungsten. A top surface 17a thereof is processed by a relatively coarse abrasive using a general polishing machine to make a course face. A cathode sleeve 18 is fitted with an internal diameter of the cup of the cathode base body 17, and is bonded and fixed by laser welding. An alkaline earth metal oxide layer 19 such as barium, strontium or calcium is formed on the coarse top face 17a by spraying method. A bonding strength of the oxide layer 19 is increased with an increase in surface area due to coarse processing, and at the same time a reaction rate of the reducer and oxide included in the cathode base body 17 increases, and activation process time in an aging process is significantly reduced.