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This combined with our resource characteristics , choose our abundant production of Panzhihua ilmenite (FeTiO 3 ) as a raw material , the carbon thermal reduction method based on the original work of carbothermal reduction method using direct preparation of low cost of Ti (C, N) powder and composite powder process optimization , in order to obtain more stable, more suitable for mass production process parameters to provide a basis for industrial production technology foundation . Through comprehensive thermal analysis, particle size analysis , X- ray diffraction analysis, scanning electron microscopy analysis methods , focusing on the ratio of raw materials , milling process , the reaction temperature and time on the reduction product Ti (C, N) effects , preferably a reasonable process parameters , and the results are discussed. The results show that : the use of high-energy ball milling mixing process can significantly reduce the carbothermal reduction temperature significantly faster reaction speed, increase the degree of reduction . The longer the milling time , the higher the degree of reduction , the milling time is too long, the process cost increases , the appropriate mixing time milling is 2 6 h. The higher the carbon content , the faster the reaction , the higher the degree of reduction . However, the carbon content is too high , it will result in reduced product of free high carbon content ; carbon content is too low , it will result in the middle of titanium oxide reduction is incomplete. Suitable raw materials ratio of FeTiO 3 : C = 1:3.25 3 .5 ( Moore ) . The higher the reaction temperature , the faster the reaction , the higher the degree of reduction ; However, the reaction temperature is too high , the reduction product difficult to disperse ; reaction temperature is too low , the reduction product of the intermediate reaction product of a large number TiO 2 , Ti 3 O 5 exists. Carbothermal reduction of ilmenite prepared Ti (C, N) composite powders suitable reaction temperature is 1300 ℃ 1400 ℃. By controlling certain parameters , you can get a good Ti (C, N) composite powders and to completely avoid intermediate oxide reduction products and the presence of free carbon . Holding time on the reaction rates of conversion and TiC 1-x N x component has a greater impact . With the holding time , the reduction product of free carbon diffraction peak and intermediate oxide Ti 3 O 5 peak decreases, suitable holding time of 2 6 h.
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