ALLOYED CATHODE AND METHOD FOR ITS DIFFUSION WELDING Russian patent published in 1995 - IPC

FIELD: electronic devices. SUBSTANCE: high-melting metal wire spiral is inserted in metallic cathode that has substrate and emissive alloy foil; spiral is wound so that its portion extending beyond foil equals half the wire diameter (1/2d) and minimum turn pitch equals 2d. Foil, substrate, and spiral are assembled for diffusion welding, mounted in shell with plastic bushing, heated in vacuum, held at pressure by pressing bushing and cathode parts back, and cooled down. Pressure is applied until temperature equal to 0.8 of welding point is applied by using two-way mechanical press-back scheme between punches and then single-way scheme is used for extruding it from space confined by shell, punches, and cathode substrate. EFFECT: improved design, facilitated manufacture. 2 cl, 3 dwg