反应烧结制备轻质高强Si_3N_4/SiC材料  

The Preparation of Light Quality and High Strength Si_3N_4/SiC Materials by Reaction Sintering

作　　者：叶飞[1] 潘丽吉[1] 刘亚[1] 郭露村[1] 

机构地区：[1]南京工业大学材料科学与工程学院,江苏南京210009

出　　处：《陶瓷学报》2012年第4期451-456,共6页Journal of Ceramics

摘　　要：采用反应烧结制备轻质高强Si3N4/SiC材料。分析了烧成制度对氮化合成Si3N4结合相的影响,研究了Si3N4结合相、SiC骨料粒径大小以及级配对试样性能的影响。通过X射线衍射仪、扫描电子显微镜、Archimedes排水法以及万能试验机分别表征材料的物相组成、微观结构、体积密度和力学性能。实验结果表明:坯料中添加大粒径SiC(D50=150μm)会增加试样的体积密度,降低试样的抗弯强度;试样中加入大粒径SiC会减少氮化增重,阻碍氮化反应;试样分别在1350℃/1450℃保温2h,生成α-SiN和β-Si3N4的量基本相等,性能最佳,抗弯强度达到125MPa,(弯曲)比强度达到5.4×104N·m/kg。Light quality and high strength Si3N4/SiC materials were fabricated by reaction sintedng. The effect of the firing system on Si3N4 phase was analyzed, and the effect of Si3N4 phase and the SiC aggregate size and gradation on the properties of samples were researched. The composition of phase and the microstructure of samples were characterized respectively by X-ray diffraction （XRD） and scanning electron microscopy （SEM）, and the bulk density and mechanical properties were characterized respectively by Archimedes method and universal test machine. The experimental results show that the bulk density of the samples were increased and the bending strength of the samples were reduced by the adding of the large size SiC（D50=150μm）. The increasing weight of samples were reduced and the nitride reactions were blocked when the large size SiC added to the samples. When the sample sintered in 1350℃/1450℃ and preserved 2h respectively, the amount of α-Si3N4 and β-Si3N4 were basic equal, and the bending strength of the sample is 125 MPa and the （bending）specific strength of the sample is 5.4 × 10^4 N· m/kg.

关 键 词：氮化硅 碳化硅 反应烧结 轻质 高强度 

分 类 号：TQ174.75[化学工程—陶瓷工业]