Abstract: A field emission cathode having a parallel array of individual electrically conductive rods of metal silicide or germanide in a silicon-based or germanium-based single crystal matrix. Each rod has an emission end exposed at one major surface of the cathode and an ohmic contact end exposed at an opposite major surface. In a preferred cathode, the matrix and rod materials are the constituents of a eutectic composition. The cathode is fabricated by a process involving producing a composite boule from a eutectic composition of a silicon-based or germanium-based material and a metal. The composite cathode body is cut from the boule so that the rods are generally normal to the major surfaces. Etching may be used to expose a uniform length of the rods at the emitting surface.

Abstract: A method of preparing electrical contacts and electrical contact materials comprises the steps of blending a conductive metallic component, such as silver, with nickel and zirconium diboride which is substantially completely free of oxides, pressing the powder mixture to form a pre-sintered compact, and thereafter liquid phase sintering the compact to a densified body.The zirconium diboride is mixed with about 2 weight percent of a reducing agent, preferably mixed carbon and boron powders, and heated to remove oxides from the surface of the zirconium diboride powder particles prior to the steps of pressing and sintering.

Abstract: An electric gas ignitor is disclosed having a gas igniting fiber comprising a core of conductive refractory material and an outer, high strength, oxidation resistant coating. One aspect of the invention concerns a primary current path defined by at least a portion of the fiber core and comprising a material having a highly uniform resistance per unit length. A substantially uniform temperature distribution is thereby promoted on the fiber surface and the formation of localized "hot spots" is inhibited. The primary current path is preferably an anisotropic material having a preferred crystal orientation which uniformly conducts electricity along the fiber length.A second aspect of the invention is directed to the inclusion of a diffusion-barrier material between the fiber core and the oxidation-resistant coating to prevent diffusion of the core and coating, which changes the fiber operating temperature and decreases its operating life.