The effect of Cu content on hydrogen reduction behavior of ball-milled -CuO nanocomposite powders was investigated. Hydrogen reduction behavior and reduction percent() of nanopowders were characterized by thermogravimetry (TG) and hygrometry measurements. Activation energy for hydrogen reduction of nanopowders with different Cu content was calculated at each heating rate and reduction percent(). The activation energy for reduction of obtained in this study existed in the ranging from 129 to 139 kJ/mol, which was in accordance with the activation energy for powder reduction of conventional micron-sized

The brazing adhesion properties of Ag coated W-Ag electric contact on the Cu substrate have been investigated in therms of microstructure, phase equilibrium and adhesion strength. Precoating of Ag layer ( in thickness) on the contact material was done by electro-plating method. Subsequently the brazing treatment was conducted by inserting BCuP-5 filler metal (Ag-Cu-P alloy) layer between Ag coated W-Ag and Cu substrate and annealing at in atmosphere. The optimum brazing temperature of was semi-empirically calculated on the basis of the Cu atomic diffusion profile in Ag layer of commercial electric contact produced by the same brazing process. As a mechanical test of the electric contact after brazing treatment the adhesion strength between the electric contact and Cu substrate was measured using Instron. The microstructure and phase equilibrium study revealed that the sound interlayer structure was formed by relatively low brazing treatment at . Thin Ag electro-plated layer precoated on the electric contact ( in thickness) is thought to be enough for high adhesion strength arid sound microstructure in interface layer.