| 摘要 |
PURPOSE:To improve a white balance after a switch is turned on by depositing Ni and Cr on alloy parts with the coefficient of thermal expansion variable depending on the degree of diffusion of Ni and Cr and by changing the temperature and time of the heat treatment for a cathode body structure to be incorporated in the center and both sides of an in-line electron gun body structure. CONSTITUTION:A tube is constituted with parts made of various metals and alloys as before, i.e., the first and second grid electrodes 41, 42 are made of Fe- Ni-Cr alloy, base metal 34 of Ni, cathode sleeve 35 of Ni-Cr alloy, cathode strap 36 of Fe-Ni alloy, cathode holder 37 of Ni-Co alloy, cathode support cylinder 38 of Fe-Ni alloy, and cathode support strap 39 of Fe-Ni-Cr alloy. An Ni layer 362 of 0.5mut or less is formed by welding or cladding on a core 361 of, e.g., 70mut and mainly made of an invar material of about 36% of Ni and about 64% of Fe to make up the cathode strap 36, which, while it is still a part, is heat treated at 800 deg.C for five minutes with a temperature difference of at least 50 deg.C between the one to be incorporated in the center electron gun and the other to be incorporated in both side electron guns under high frequency heating by use of a completed cathode body structure or a completed cathode incorporated in a color picture tube. |
