Abstract: Method of fabricating structures, such as parts for use in nuclear power generation systems, are described herein. A representative method of fabricating a part for a nuclear reactor system includes additively manufacturing the part as a monolithic structure from a wire formed of an oxide dispersion strengthen (ODS) material, which includes an oxide material dispersed within a metal material. Specifically, the method can include directing a beam of thermal energy toward the wire to melt the wire, and permitting the melted wire to cool and solidify to form the part such that the oxide material remains substantially dispersed within the metal material. By maintaining the dispersion of the oxide material within the metal material, the ODS material can retain a good creep resistance, wear-resistance, corrosion resistance, and/or other ODS material property at elevated temperatures—even after fabrication.

Abstract: Heat pipes and methods of forming heat pipes, such as for use in nuclear reactor systems, are described herein. A representative method of forming a heat pipe includes forming a first wicking structure from a first material and forming a second wicking structure on the first wicking structure. Forming the second wicking structure can include mixing a second material and a third material, and heating the mixture of the second material and the third material to a temperature (a) less than a melting temperature of the second material and (b) greater than a melting temperature of the third material to melt the third material. The method can further include cooling the mixture of the second material and the third material to below the melting temperature of the third material such that the third material solidifies to bond together a plurality of particles of the second material into a porous structure.

Abstract: Power generation systems, such as nuclear power generation systems, are described herein. A representative power generation system includes a heat source, a heat pipe, and a thermophotovoltaic cell. The heat pipe includes a first region and a second region. The first region is positioned to absorb heat from the heat source, and the second region is positioned to radiate at least a portion of the absorbed heat away from the heat pipe as thermal radiation. The thermophotovoltaic cell is positioned to receive the thermal radiation from the second region of the heat pipe and to convert at least a portion of the thermal radiation to electrical energy. The power generation system can further include another heat pipe positioned to remove waste heat from the thermophotovoltaic cell.