Thermionic emission characteristics of sintered tungsten-rhenium alloys
Tóm tắt
Multiconstituent refractory metals, capable of operating at high temperatures, provide greater heat rejection, hence lighter, denser and more efficient thermionic energy converters. Thermionic energy conversion offers unique advantages such as increased power levels and densities which are prime requisites for crucial future space applications. Investigation of these multiconstituent metals for efficient thermionic energy conversion is the object of the present research activity. Tungsten, being the most refractory metal, has received extensive investigation because of its compatibility in thermionic nuclear reactors, but its brittle nature limits its utility in critical applications. In the quest to obtain enhanced bare work functions and increase its utility, tungsten was alloyed with rhenium and the effect of alloying on its recrystallization and thermionic emission characteristics has been studied here with the help of a unique thermionic emission microscope. The thermionic emission results obtained with the four sintered tungsten, rhenium alloys will be used as a basis to develop new insights into the correlation of experimentally obtained thermionic properties with pertinent material properties.
Tài liệu tham khảo
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