【摘要】 通过液相磁力搅拌混合原料粉末钛、铝、石墨以及少量锡,压片后在1300~1400℃无压烧结合成了三元Ti3AlC2陶瓷。研磨粉碎后样品的X射线衍射(XRD)结果表明,在1300和1350℃烧结30 min,可以得到Ti3AlC2相,同时存在Ti2AlC相和TiC相的粉体。原料粉末为3Ti∶1.0Al∶1.8C∶0.2Sn的样品在1400℃烧结30 min后研磨,可以得到纯度较高的Ti3AlC2粉体,扫描电镜照片显示合成的Ti3AlC2为层状结构,厚度约在50~100 nm。结合差示扫描量热曲线和XRD图谱对合成反应机理进行了初步探讨,表明原始粉末首先在铝熔池中反应生成钛铝金属间化合物,随着温度的升高,生成有TiC,钛铝金属间化合物与石墨、TiC继续反应,最终合成Ti3AlC2。更多还原

【Abstract】 The ternary carbide Ti3AlC2 ceramics was snthesized by pressure-less sintering the compressed circular disk,made of a mixture of Ti,Al,graphite,and a small amount of Sn powders,in 1300~ 1400℃ range in argon atmosphere.The impacts of the sintering conditions on the microstructures and phase structureswere evaluated.The powders, from the sintered disk,were characterized with X-ray diffraction and scanning electron microscopy.The results show that the sintering temperature has a major impacton the microstructures and phase-strures.For instance,simtered in the 1300 ~ 1350℃ range for30 min,Ti3AlC2phase was found to coexistwith Ti2AlC and TiC phases.Highly pure,Ti3AlC2lamina grains,50~ 100 nm in thickness.were observed in the powders,obtained by grinding the disk sintered at 1400℃ for 30 min,and with a mixture of 3.0Ti∶1.0Al∶1.8C∶0.2 Sn as the starting materials.Possible mechanisms responsible for the formation of Ti3AlC2were also tentatively discussed.更多还原