碳源对AlON粉体合成及其透明陶瓷制备的影响

Effect of Carbon Sources on Synthesis of AlON Powder and Fabrication of Transparent Ceramics

以纳米炭黑、微米碳粉为碳源,采用碳热还原法合成AlON粉体和无压烧结制备AlON透明陶瓷。利用X射线衍射仪、扫描电镜、颗粒度分析仪和分光光度计等研究碳源对粉体及陶瓷制备的影响。结果表明：碳源尺寸及形貌与AlON粉体的合成温度、粉体形貌及颗粒大小密切相关;采用纳米炭黑降低了AlON粉体的合成温度,在1730℃合成了单相粉体;采用微米碳粉在1750℃煅烧2h条件下制备了高纯度的AlON粉体,从而制备了高透光率的AlON陶瓷,该样品（1mm厚）在1000~5000nm波长范围内的直线透过率在80%左右,在3.93μm波长处光学透过率最高可达83.7%,其平均晶粒尺寸为110~120μm。

Nanosized carbon black and micron carbon powder were used as the carbon sources to synthesize AlON powders by carbothermal reduction method and prepare transparent AlON ceramics by the synthesized AlON powders through pressureless sintering.Effects of the carbon sources on the synthesis of the AlON powder and the fabrication of the transparent ceramics were investigated by XRD,SEM,particle size analyzer and spectrometer.The results show that the size and the morphology of the carbon sources are closely related with the calcining synthetic temperature,the morphology and the particle size of the obtained AlON powder greatly.The addition of the nanosized carbon black decreases the calcination temperature to 1730℃ at which the single phase AlON powders are synthesized.High purity AlON powders prepared by the micron carbon powders calcined at 1750℃ for 2hours are used to fabricate the highly transparent AlON ceramics.The in-line optical transmittance at1000-5000 nm wavelength of the AlON ceramic sample（1mm-thick）is almost 80%,with the max transmittance of 83.7% at 3.93μm wavelength.The average grain size of the obtained AlON transparent ceramics is in range of 110-120μm.