Conducting Aluminum-Filled Nylon 6 Composites

摘要

This work is concerned with the preparation and characterization of composite materials prepared by compression molding of a mixture of aluminum flakes and nylon 6 powder. The electrical conductivity, density , hardness and morphology of composites were investigated. The electrical conductivity of the composites is < 10-11 S/cm unless the metal content reached the percolation threshold, beyond which the conductivity increased markedly by as much as 1011. The volume frac- tion of conductive filler at the percolation threshold was calculated from experimen- tal data, by fits to functions predicted by the percolation theory. Decreasing the av- erage particle diameter of filler leads to increased percolation threshold (it varies from 23 to 34 vol% for the three different fillers studied) and decreased maximal conductivity of composites. The density of the composites was measured and com- pared with values calculated assuming different void levels within the samples. Furthermore, it is shown that for certain sizes of particle filler, the hardness de- creases initially with the increase of metal concentration, possibly because of poor surface contact with the nylon matrix, but, starting from a ,certain value, there is a hardness increase. For the smallest particle filler, the har~ness of samples is not influenced by the presence of the filler .