生物形态多孔氮化钛陶瓷的碳热氮化法制备

Porous Biomorph-genetic TiN/C Ceramics by Carbothermal Reduction-Nitridation Using Beech Wood

研究了以生物模板(木炭)浸渍TiO2溶胶,高温碳热-氮化制备TiN陶瓷的工艺过程。应用热力学原理计算了经溶胶浸渍后形成的TiO2／C复合体系的氮化条件,确定了N2,CO分压对氮化温度的影响。采用碳热氮化法,在高浓度的氮气压力下反应烧结制备了具有生物形貌的多孔TiN／C陶瓷。结果表明:在1400℃,4 h,0．5 MPa氮气压力下,得到了具有立方晶体结构的TiN／C多孔陶瓷,并保留了木材模板的显微结构。

A porous titanium nitride ceramics with a biomorphic microstructure was prepared at 1400℃ for 4h by carbothermal reduction and nitridation of TiO2/C composite under high concentration nitrogen atmosphere（0.5MPa）, These composites were prepared using beech wood impregnated with titania sol by vaccum/pressure infiltration process. The nitridation conditions of the TiO2/C composite were analyzed by thermodynamic calculation. Microstructural observation and phase structure of as-obtained woodceramics were performed by scanning electron microscopy and X-ray diffraction, respectively. Experimental results showed that The resultant porous TiN/C ceramics had the same external and internal forms of the original wood.