Composite spray coatings containing Al2O3 and AlN were prepared and their tensile bonding strength, microhardness, corrosion behavior and thermal conductivity were compared to those of pure Al2O3. The goal of this study was to identify a spray coating with an improved thermal conductivity over that of Al2O3 for use in coating heat exchangers, furnace walls, heat pipes, etc. The coatings that were prepared had AlN : a-Al2O3 ...
Thermophysical properties of a uranium-6 wt. % zirconium alloy were investigated at high temperatures to evaluate the performance of the alloy as a driver fuel for a liquid-metal cooled fast reactor. Of particular interest to the authors were the coefficient of thermal expansion, the specific heat, and the thermal conductivity of the alloy....
Zr-Cu-Al metallic glasses were formulated with differing compositions to determine their thermophysical properties. It was determined that by decreasing the zirconium content of the metallic glass, the thermal conductivity can be increased. The maximum value of thermal conductivity was found for the metallic glass with a composition of Zr:Cu:Al = 50:39.3:10.7 (at. %). It was found that although the metallic glasses did not crystallize with heat treatment below Tg, they did ...
Calcium is partially substituted by bismuth in the Ca3-xBixCoO9+delta (x=0.00, 0.05, 0.10, 0.15, 0.20, and 0.30) system in order to determine how this substitution affects the thermoelectric and magnetic properties of the system. It was determined that the system had a positive thermopower, and thus the main carriers were holes. A maximum thermoelectric figure of merit of 0.091 was achieved with the Ca2.7Bi0.3CoO9+delta sample. The magnetic property test results indicated that ...
Calcium is partially substituted by bismuth in the Ca1-xBixMnO3-delta (x=0.00, 0.02, and 0.05) system in order to determine how this substitution affects the electrical resistivity, thermopower, and thermal conductivity. The experimental results were then used to calculate the thermoelectric figure of merit for each sample. The highest observed figure of merit was 0.047, which represented a 487% increase over the unsubstituted sample....