蓝晶石原位合成氮化铝结合碳化硅复相材料

In-situ Synthesis of AlN/SiC Multiphase Ceramics from Kyanite

以天然矿物蓝晶石为原料,通过碳热还原氮化法(CRN)原位合成AlN结合SiC复相材料。通过将不同配比的原料与石墨混合(根据成分比例设定为30%和35%),在氮气气氛下分别于1500、1550和1600℃下进行烧结,确定了最佳的烧制温度为1600℃。在最佳烧结温度下进一步对比25%、30%和35%的不同石墨加入量的烧成结果。分别通过XRD和SEM对烧结后的样品进行物相分析和微观形貌表征,并分析样品中AlN和SiC的含量。结果表明,石墨还原剂的最佳添加量为25%。

Using the kyanite as raw material, AlN/SiC multiphase ceramics was synthesized with the carbothermal reduction nitridation （CRN） method. Different ratios of graphite were added into the kyanite （30% and 35% according to the component of the kyanite used in this experiment）. Then the green bodies were sintered in a nitride atmosphere at 1500, 1550 and 1600 ℃. The optimal sintering temperature was 1600 ℃ according to the XRD pattern analysis of the sintered bodies. Then the graphite addition ratio was decreased to 25%. Different ratios of graphite addition were compared among 25%, 30% and 35%. The major phases and microstructure of the sintered bodies were studied by XRD and SEM. The component of the AlN and SiC were analyzed. The result shows that the optimal graphite ratio was 25%.