Gold colloids were prepared by electrical explosion of wire in various media: cold water (0 degrees C), room temperature water (25 degrees C), hot water (80 degrees C), 0.01 M polysorbate surfactant 20 (TW 20) solution, mixture of 0.01 M TW 20 and 0.01 M ascorbic acid. The size distribution of nanoparticles measured by transmission electron microscope was found to shift to a smaller size with a decrease of temperature and a presence of TW 20 surfactant. The multiple light scattering results showed that medium temperature and ambient medium of explosion process is much influence on the stability of colloid. The gold colloid prepared in cold water is unstable in comparison with one prepared in warm and hot water. The best stability of gold colloid obtained with explosion medium of TW 20 and ascorbic acid solution.

Copper-graphite nanocomposites containing 5 vol.% graphite were prepared by a powder metallurgy route using an electrical wire explosion (EEW) in liquid method and spark plasma sintering (SPS) process. Graphite rods with a 0.3 mm diameter and copper wire with a 0.2 mm diameter were used as raw materials for EEWin liquid. To compare, a pure copper and copper-graphite mixture was also prepared. The fabricated graphite was in the form of a nanosheet, onto which copper particles were coated. Sintering was performed at 900 degrees C at a heating rate of 30 degrees C/min for 10 min and under a pressure of 70 MPa. The density of the sintered composite samples was measured by the Archimedes method. A wear test was performed by a ball-on-disc tribometer under dry conditions at room temperature in air. The presence of graphite effectively reduced the wear of composites. The copper-graphite nanocomposites prepared by EEW had lower wear rates than pure copper material and simple mixed copper-graphite.

Fe-36Ni alloy nanopowder was prepared via electrical explosion of wire in DI water. The nanopowder was reduced in hydrogen at 500 degrees C for 30 min. Spark plasma sintering at 800 and 1000 degrees C for 10 min was used to obtain bulk samples from the hydrogen-reduced nanopowder. The sintered samples were annealed at 500 degrees C for 2 h. X-ray diffraction was used to analyze the phases of the nanopowder and sintered samples. The results showed that the sintered samples were formed in gamma-(Fe-Ni) solid solution. The particles sizes and morphologies of the as-synthesized and hydrogen-reduced nanoparticles were observed via transmission electron microscopy. The morphologies of the as-synthesized nanoparticles had spherical core-shell structures. Core was gamma-(Fe-Ni) and the shell was FeO. The nanoparticles of the as-synthesized and hydrogen reduced samples were found to be nearly spherical in shape, with average diameters of 32 and 70 nm, respectively. The hysteresis loops of the as-synthesized nanopowder, hydrogen reduced nanopowder, and sintered samples revealed ferromagnetic characteristics.

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