Preparation and characterization of Mo-15 Cu superfine powders by a gelatification-reduction process

Mo-15 wt.%Cu composite powders were synthesized by a gelatification-reduction process, in which precursor gelcasts were obtained by adding an initiator into a suspension containing ammonium heptamolybdate, copper oxide, acrylamide organic monomer and some additives. The gelcasts were then calcined and hydrogen-reduced to convert into Mo–Cu powder. Phase constitution and morphology of the gelcasts, the calcined powder, as well as the resulting Mo–Cu powder were characterized. Density and microstructure of the sintered Mo–Cu parts were checked to investigate sinterability of the Mo–Cu powder. It was shown that the gelatification-reduction process produces superfine Mo–Cu powder with particle size of about 100 nm. The Mo–Cu powder shows good sinterability. Relative density of 99.59% of the theoretical is achieved for Mo–Cu powder compacts sintered at 1150 °C in H2 atmosphere. Furthermore, the sintered Mo–Cu parts exhibit excellent physical and mechanical properties. Maximum electrical conductivity is 41.75%IACS. Bending strength and Vickers hardness for Mo–Cu compacts sintered at 1150 °C were 833.65 MPa and 300.15 MPa, respectively.