ИСТИНА

History of carbon cathode materials is a history of upgrading and advancements. There are different philosophies of applications of different grades and compositions of cathode carbon blocks. From the point of view of materials science and processing of carbon cathode materials, there are some questions to be defined. - Volume effect transformations in course of processing and service. In graphitic blocks, the anthracite in service slowly transforms to carbon with volume decrease and the porosity of blocks should increase; this may open way to enhanced bath flow through the pores. - From scientific point of view, the degree of graphitization of the synthetic graphite in cathode blocks and its influence on performance is interesting. - Fracture properties of carbon cathode blocks might be improved, since carbon cathode blocks have elasto-plastic fracture behavior. Yet, it is doubtful that this research will contribute to better models of cathode life prediction. - Intercalated sodium may move in the lattice of cathode carbon block. The comparison of the velocities of the movement of sodium in the cathode carbon block towards refractory and of the movement of cryolite in the permeable pores of the block are still unknown. - Clarification for the mechanism of sodium swelling of the carbon cathode block is of scientific interest. - The problem of the minimization of the cryolite