Use of a special, high stiffness precision turning machine with a polycrystal cubic boron nitride tool bit promises to allow cathode emitter surface finishing free, or at least freer, of the smearing, tearing, and eplastic flow of cathode material (sintered tungsten) common to conventional process. Microscopic comparison of a conventional dispenser cathode surface finish using a hardinge lathe and a tungsten carbide tool bit, with a precision finished cathode, showed the precision finished surface apparently free of tungsten crystal damage. This process promises to improve both uniformity of sintered tungsten porosity and an improved work function. The process is the subject of a patent application and all rights thereto are reserved.
