Lamps and discharge devices and materials therefor

摘要

Conducting cermets with volume fractions of nickel down to 0.045 are produced by coating relatively coarse refractory oxide granules with fine metal powder particles and compacting and sintering the coated granules. Using oxide granules in the size range 400 to 800 microns it is possible to make conducting cermets having the same volume fraction of metal and thus the same thermal expansion coefficients as insulating cermets prepared from finer granules of the same oxide. The cermets can be used to fabricate tubes and components for electric lamps and may include integrally formed conducting and insulating regions.