Nanostructured Cu-Al_2O_3 composite produced by thermochemical process for electrode application

摘要

Nanostructured Cu-Al_2O_3 composite powders were synthesized by thermochemical process. The synthesis procedures are (1) preparation of precursor powder by spray-drying of solution made from water-soluble copper and aluminum nitrates, (2) air heat treatments to evaporate volatile components in the precursor powder and synthesis of nanostructured CuO+ Al_2O_3, and (3) CuO reduction by hydrogen into pure Cu. The suggested procedures stimulated the formation of the gamma-Al_2O_3, and different alumina formation behaviors appeared with various heal-treating temperatures. The mean particle size of the final Cu-Al_2O_3 composite powders produced was 20 nm, and the electrical conductivity and hardness in the hot-extruded bulk were competitive with Cu-Al_2O_3 composite by the conventional internal oxidation process.