真空原位碳热还原法制备纳米碳化钛粉体

分别以钛酸四丁酯和蔗糖为钛源、碳源,采用溶胶—凝胶法制备前驱体并在真空条件下原位碳热还原制备纳米碳化钛。采用X射线衍射仪和扫描电镜对产物物相、形貌进行分析,并根据谢乐公式计算所得TiC晶粒尺寸。结果表明:在1 300℃的真空碳热还原条件下能够得到纳米碳化钛,随着碳含量的增加碳化钛的纯度提高,晶粒尺寸减小;随碳热还原温度从1 300℃升高到1 500℃,碳化钛的形貌由长径为100 nm左右的长条状变为粒径为20~30 nm的球形颗粒,但TiO相含量相对增加。

Preparation of Nano-TiC Powders by In-situ Carbothermal Method in Vacuum

Nano-titanium carbide (TiC) was prepared by in-situ carbothermal reduction under vacuum condition using the precursor synthesized by sol-gel method with tetrabutyl titanate (Ti (C4H9O)4) and sucrose as titanium and carbon sources,respectively.X-ray diffraction and scanning electron microscope were respectively employed to analyze the phase composition and morphology of the obtained samples,and the size of the TiC crystals was calculated by Scherrer formula from the XRD data.The results show that nano-TiC can be synthesized at 1 300 ℃ in vacuum,and the purity of TiC increases while the crystal size decreases with increase in carbon content.When the carbothermal reduction temperature increases from 1 300 ℃ to 1 500 ℃,the morphology of TiC changes from long bars with about 100 nm of size to sphere particles with 20 ～ 30 nm of diameter,but the phase content of TiO is increased unexpectedly.