STANDARD CATHODE AND ITS MANUFACTURE

摘要

PURPOSE: To improve an emission characteristic of a scandate cathode by containing a scandium compound or scandium alloy capable of showing scandium segregation in an upper layer of a cathode main body. CONSTITUTION: A cathode main body 13 has an upper layer 23 and an emitting surface 33. This cathode main body 13 is obtained by pressurizing a matrix of W powder to the upper layer 23. In this case, the matrix is composed of W powder and a scandium compound or scandium alloy powder, and a sintering operation is performed in a hydrogen atmosphere after compression. This scandium compound or scandium alloy shows scandium segregation at an operating temperature of a cathode or at an activation temperature higher than the operating temperature. Therefore, after being assembled into a cathode-ray tube, an extremely high cathode load and activation of the cathode become possible.