| TC4(Ti-6A1-4V) titanium alloy is the most widely used typical α+β type titanium alloy which accounts for all of titanium alloys75%～85%. The near a Ti8LC (Ti-6Al-1.7Fe-Mo) and the near βTi12LC (Ti-4.5Al-1.5Fe-6.8Mo) two low-cost titanium alloy developed, using inexpensive iron instead of the more expensive alloying elements vanadium for the purpose to reduce the production cost and improve the room temperature tensile performance basing on TC4titanium alloy, by the Northwest Research Institute of nonferrous metals. The two kinds of new titanium alloys will have a great application potential.The conventional preparation process of the Ti8LC and Til2LC alloys:the Al-Mo alloy, the Fe-Mo alloy and the titanium sponge mixed firstly and compressed into electrode, and gained the products afterward by vacuum arc melting method. Titanium sponge prepared by the Kroll method, the Kroll method has many disadvantages such as complex process, uncontinuous production, low productivity, high costs, and environmental pollution etc., lead to high production costs of titanium sponge. And the Al-Mo alloy and Fe-Mo alloy were prepared by metal-doped each other method, respectively, resulting the Ti8LC and alloy preparation process complex, besides, equilibrium partial pressures of the alloy elements varied greatly, resulting inalloying elements volatile loss, affecting the measurement of the ratio of the titanium alloy. And have led to high production costs in T18LC and Ti12LC alloys from the above all reasons mentioned. The molten salt electrolysis preparation process of the Ti8LC and Ti12LC alloys:the MoO2, Al2O3, Fe2O3, and TiO2as raw materials by a certain mixing ratio, pressing and sintering the preparation of the cathode, and high-temperature molten salt electrolysis to obtain. So the process is simple, low cost, and oxides are solid-phase deoxy electrolysis process is not easy to loss of alloying elements.In this paper, the two kinds of low cost titanium alloys were prepared by molten salt electrolysis, and the electrolysis process was also studied, all for the purpose to provide a preparation theoretical basis of the two kinds of titanium alloys by molten salt electrolysis. The main results are as follows.1. The Til2LC alloys were prepared successfully under the condition of CaO-undoped and18wt%CaO-doped, and the deoxygenation process was also studied.The CaO-undoped cathodic reaction process:the CaTiO3low-valence oxide Ti6O, Ti2O and Ca2Al2O5were formed firstly. With the deoxy time increasing, the content of low-valence titanium oxide increase, followed by appearing of the metal molybdenum, then Til2LC alloy phase appeared with the continuing of deoxygenation. The final electrolysis product after8h was composed of the Til2LC and a small amount of CaTiO3and Ti6O. And the oxygen content of sample is25.74wt%. The18wt%CaO-Doped cathode reaction process:CaTiO3, Mo, CaCO3, low-valence oxide Ti2O, Ca2Fe2Os, Ca2Fe7O11and Ca3Al2O6were formed firstly. With the deoxy time increasing, the content of low-valence titanium oxide increase, and alloy phase α-Ti generated, followed by β-Ti and TiO, and then then Til2LC alloy phase appeared with the continuing of deoxygenation. The final electrolysis product after8h was composed of the Til2LC alloy phase. And the oxygen content of sample is11.5wt%. The cathodic doping CaO deoxy significantly faster than the doped CaO cathode electric deoxy speed.2. The effects of cathode preparation technology on cathode performance and electrolytic preparation of Til2LC alloys were studied. The results showed that Al in electrolytic products distributed uniformly when the grain diameter was less than15um and cathode sample had the best effect when the compacting pressure was5MPa and the sintering time was6h.3. The exploring and preparing of Ti8LC alloys had accomplished successfully. |
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