With ABS resin as the matrix material and nickel-coated glass fibers as the conductive filler, continuous kneadings of composite conductive plastics were performed under various operating conditions. The kneaded materials were evaluated by measuring their electric conductivity and the shielding effectiveness. Also, the dispersion states of the fillers in the kneaded materials, that is, the formation states of conductive paths by the fillers, were studied in terms of homogeneity, direction and the length of the fillers in the matrix resin. Based on the results, the relationship between the conductivity and the dispersion state of the fillers in the composite conductive plastics was discussed.
Finally, the dispersion state of the fillers in the matrix resin was related to the hold-up of the kneading materials.

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A granular medium is idealized here by a model composed of stress/strain field deviations in a random continuum. Total stress-strain relationships for this model are derived by integrating incremental relationships. Further more, the theory is developed to explain the influence of the dispersion of internal microstress, initial elastic strain, and local yield stress on the macroscopic behavior of a granular medium. Predictions of the theory are reported and agree with the results of the experimental work.

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The coating of metal particles with ceramics by a mechanofusion process were investigated for application to the production of high-temperature materials, wear-resistant materials and functionally gradient materials. Composite particles of SUS 316L/PSZ, SUS 304L/Si₃N₄ systems were manufactured by a mechanofusion process. The process of composition and sintering structure that were generated using these composite powders were discussed by using optical microstructure, a scanning electron microscope and X-ray analysis.

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Adhesive forces of sub-micron particles of limestone were measured by using a split-cell type tensile strength tester under various vapor pressure conditions of water, ethanol and acetone. The adhesive force generated by ethanol vapor or acetone vapor adsorption was smaller than that generated by water vapor adsorption.
Agglomerated particles generated from a micro-fluidized bed of the limestone sample with various atmospheric gases were dispersed by a high speed gas stream through a small pipe, and the size distribution of the agglomerates was measured. The agglomerates containing adsorbed ethanol were easily dispersed into the single particles by about half the force required for the agglomerates containing adsorbed water, which qualtatively corresponded to the decrease in the adhesive force of the particles by adsorbing ethanol vapor instead of water vapor.

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Ultra-fine grinding and simultaneous surface treatment of magnetite particles were examined by a high-speed media agitating mill using zirconia balls of about 0.6mm diameter in decane. Oleic acid was used as the surface treatment agent.
Well-dispersed ultra-fine particles were obtained. More than 10mol% of oleic acid was necessary to produce Ultra-Fine Magnetite Particles (UFMP). Hematite ultra-fine. particles were produced if oleic acid was less than 5mol%. The weight in percent of the ultra-fine particles produced increased with the increase in grinding time up to 10hr and became almost constant above 10hr.
The magnetic fluid made up of the obtained UFMP had almost the same magnetic susceptibility as that of UFMP produced by other methods, such as chemical synthesis.

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A fine α-alumina powder was coated by SiO₂ ultra fine particles with a diameter of nano-meters. SiO₂ by hydrolysis of ethyl silicate with water adsorbed on the powder was precipitated onto the powder in the hydrophobic liquid which contained 90vol.% ligroin, 10vol.% ethyl silicate and 0.015mol/l stearic acid. The thickness of the coated layer was controllable by changing the amount of the adsorbed water up to 10wt.% of the powder.

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