| 摘要 |
PURPOSE:To obtain a manufacturing method of an impregnate type cathode frame with exceedingly good dimensional accuracy by providing a process in which the surface layer section of a porous tungsten substrate section is impregnated with copper or plastics and a process in which the porous tungsten substrate section the surface layer section of which is impregnated with copper or plastics is precisely cut and processed into a preset shape. CONSTITUTION:A cap 17 obtained by press-molding a copper plate of some 0.1mm. in thickness is fit to the exposure section of a porous tungsten substrate section 14 and only the top surface layer of the porous tungsten substrate section 14 is impregnated with copper using a high frequency electric furnace. Then a section of only top surface layer of the porous tungsten substrate section 14 im pregnated with copper is precisely finished based on a cathode support cylinder 11. Subsequently, the copper used for impregnating of the surface is removed. Since this copper exists only on the top surface of the porous tungsten substrate section 14, it can be removed in an extremely short time. As a result, the porous tungsten substrate section 14 can hardly be deformed. |
