Electrical conduction of metal nanoclusters by percolation is a very interesting area in nano-device. For more functional nano-sensors consisting of multiple nanocluster blending film, various metals, such as Cu and Ni nanocluster films were fabricated using inert-gas condensation method. The percolation threshold of the films was measured. In addition, for the operation of sensors using these nanocluster films in air, aging experiments of the percolated films in air were carried out. While the percolation threshold was in connection not with the material species but with the area coverage of nanocluster films, the conductive characteristics according to the aging temperature depended on the material species. Reversible and irreversible conduction behaviors of nanocluster films were investigated with nanoscale microstructures using electron microscopes.

Combustion synthesis of titanium borides from Ti and B binary powder mixtures having molar ratios B/Ti of 1.9 to 2.4 resulted in the formation of TiB2 as the primary phase and TiB as the secondary phase. The amount of TiB decreased when the particle size of the Ti in the powder mixtures became small and when the B content was increased. The results are discussed in terms of the homogeneity of reactant powder mixtures and the degree of boron saturation of the Ti-B melt. The burning rate increased from 11 to 15 mm/s as the titanium particle size decreased from −100 to −325 mesh with the same boron particle size of –325 mesh.