Ti Base Of Tib <sub> 2 </ Sub> Diffusion Layer Material In Aluminum Electrolytic Inert Cathode

Based on extensive literature review and previous work in the research of TiB2 cathode materials in aluminum electrolysis, innovational investigation was performed, in which the TiB2 boronizing layer on Ti matrix was used as cathode materials for aluminum electrolysis.First, through improvement of traditional Ti boronizing method, TiB2 boronizing layer on Ti matrix was prepared successfully with B4C-borax powder pack-boriding. Thermodynamic analysis of boronizing reaction demonstrated the feasibility.Effect of powder component and proportion on the result had been studied as the thickness, Surface morphology and combinability of boronizing layer considered. The optimum proportion of B4C , Na2B4O7, KBF4, SiC powder mixture was 30:10:3:7(wt%).Systemic research on effect of experiment condition on the phase structure and thickness of boride layer has been discussed. Result show that experiment temperature and heat-treated duration have a great influence on the phase structure and thickness of TiB2 layer. As the temperature rising within 900C~1000C, the thickness of layer increases quadratically and with the heat-treated duration extending, the thickness have linear relation with the square root of duration. At the same time, detrimental hole and crack at joint of matrix and TiB2 layer disappeared after the pre-annealing process being used. The final TiB2 layer has integrative structure and even thickness which arrives 78 um.Measurement of TiB2 layer properties show that TiB2 boronizing layer has great wettability of liquid aluminum thermal shock resistance corrosion resistance about liquid aluminum and electrical resistivity (18. 8u cm average), which qualify the TiB2 boronizing layer to applied for aluminum electrolysis.Practicability of TiB2 boronizing layer as cathode has been examined by simulative aluminum electrolysis within 60-90minutes. Results show that TiB2 layer cathode has great wettability of liquid aluminum, integrative structure and resistance against aluminum corrosion. At the same time, it is also found that TiB2 boronizing layer has ideally resistance against sodium penetration, which is better than other kinds of cathode materials used present-day. In a sum, TiB2 boronizing layer has great developable potential as new style wettable inert cathode of aluminum electrolysis.