| TiC has high melting point, high hardness, high wear resistance. And then it is widelyused as abrasive or cutting tools, and even reinforcement for composite materials. WhileTi(C1-xNx) is a continuous solid solution formed by TiC and TiN, which is a kind of superiorperformance and extensive use of refractory oxide materials with a high melting point, highhardness, great corrosion resistance and oxidation resistance, besides good conductive heatresistance. And it’s suitable for chemical, electronic, mechanical, aerospace, automobilemanufacturing and other fields. Ultrafine powder generally refers to a range of ultrafinematerials whose grain sizes are from nano to micron. The preparation of ultrafine powder hasfurther improved TiC and Ti(C1-xNx) application, which has extremely broad prospects. Atpresent most of particle sizes about industrialized preparation of TiC powder are25μm, and24μm for Ti(C1-xNx) powder. Along with the development of modern industry, industrydemands for ultrafine TiC and Ti(C1-xNx) powder are more and more big. While commercialnano TiC and Ti(C1-xNx) powder price is from3500yuan/kg to5000yuan/kg, which is soexpensive. And reducing the costs of research on ultrafine TiC and Ti(C1-xNx) powderpreparation technology has great practical significance.The way on synthesis of ultrafine TiC and Ti(C1-xNx) powder has taken Ti（OC4H9）4astitanium, carbon black or organics that took high temperature cracking reaction as carbon, andmixed them by magnetic stirring dispersion technology to get precursors through sol-gelmethod, which was analysed by TG-DSC and reaction mechanism. And it shows that thetemperature for this reaction should be above1427℃. This paper also studies the influencebetween different process parameters, which include raw materials, charge ratio, temperatureand time, and product performance such as phase, particle size, as well as powder morphologyand composition. It shows that nano superconductive carbon black and phenolic resin hasbeen used as carbon for research. Beyond that the best charge ratio, temperature and time canbe confirmed, which is1500℃for1hour.Ti（OC4H9）4in water can be hydrolyzed to Ti（OH）4, which belongs to sol-gel process, andit can be refined raw materials. Before the sol-gel, it need stir for a period of time with carbon,which could achieve the purpose of spatial dispersion for reactants through sol-gel to get theprecursor. However, ultrafine TiC and Ti(C1-xNx) powder with an average particle size about200nm can be prepared by carbon thermal reduction. After precursor prepared by Phenolicresin and Ti（OC4H9）4through sol-gel, it can provide carbon by high temperature crackingreaction. And then the ultrafine TiC and Ti(C1-xNx) powder with an average particle size lessthan200nm can be prepared by carbothermal reduction, which is rarely reported in the areas of TiC and Ti(C1-xNx) preparation as a new way on synthesis of ultrafine TiC and Ti(C1-xNx)powder. Usually preparation of precursor by sol-gel can improve the mixing uniformity ofraw materials, which mixing effect is better than that of ball mill mixing. Moreover, thehigh-purity ultrafine TiC and Ti(C1-xNx) powder can be prepared at1500℃for1hour with thebest charge ratio. Compared to the process about preparation of TiC and Ti(C1-xNx) by organiccarbon and inorganic carbon, organic carbothermal reduction process is more complicated,which reflects that organic can take a series of complex broken chain reaction and molecularstructure rearrangement at a low temperature. But cracking reaction of the organic hasbasically been over at1000℃. In the end, organic resolves to provide with great activatedcarbons. And the particle size of TiC and Ti(C1-xNx), which is prepared by organic, is morefiner than that prepared by inorganic carbon black, respectively from175to210nm and200to230nm. |
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