Papers by Keyword: Compact Pressure

Abstract: By detecting microstructures and properties of Cu-W composites, effects of powder composition, sintering temperature and compacting pressure on sintered billets were studied, and sintering mechanism of Cu-W powders was discussed. Effective rules of process parameters have been preliminarily obtained: Sintered billets of Cu-40W and Cu-50W had a low density when compacted at 200MPa, sintered below the melting point of copper, and density, hardness enlarged with sintering temperature increasing; Hardness, density, electrical conductivity of Cu-40W enlarged with compacting pressure when compacted above 600MPa, sintered at 1100°C; But when compacted at 800MPa, sintered at 1100°C, Cu-40W sintered billets had a density of 11.37g/cm3, relative density of 99.6%, closed to the theoretical value.

Abstract: Self-propagating high-temperature synthesis with reduction process was used to fabricate LaB6 ceramic powder from La2O3-B2O3-Mg system. The combustion reaction carried out in inert atmosphere (Ar) and the combustion temperature was about 1600°C. The products were washed with dilute hydrochloric acid and distilled water, respectively, to remove LaBO3, Mg3B2O6, MgO and other impurities. The influence of compact pressure and addition of SHS diluent on the grain size was studied. The result indicates that as the compact pressure increased, the mean size of powder decreased gradually. The addition of diluents reduced the synthesis temperature, and as the amount of diluent increased, the grain size of LaB6 powder was found to reduce continuously. Microstructure analyses show that the mean grain size of LaB6 powder prepared by SHS with reduction process is less than 500 nm, which is finer compared with the grain size prepared by traditional process.