中國有色金屬學(xué)報(bào)(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 25 No. 11 November 2015 |
（1. School of Metallurgical and Ecological Engineering,
University of Science and Technology Beijing, Beijing 100083, China;
2. State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China）
Abstract:The ambient electrical conductivity (AEC) of carbon cathode materials was investigated in respect to their open porosity, crystal structure and graphite content using hydrostatic method, four-probe technique and X-ray diffraction (XRD), respectively. The AEC is proportional to the specific conductivity (σ0) and the exponential of (1-ε) (ε is porosity) by a quasi-uniform formula based on the percolation theory. The σ0 can reflect the intrinsic conductivity of the carbon cathodes free of pores, and it depends on the mean crystallite size parallel to the layer (002). The exponent n is dependent on the materials nature of the cathode aggregates, while an averaged value, 4.65, can practically work well with 5 types of cathode materials. The calculation of σ0 can be extended to the graphitic cathodes containing different aggregates using the simple rule of mixture.
Key words: carbon cathode; electrical conductivity; porosity; crystal structure; aluminium reduction cell
