放电等离子快速烧结SiC晶须增强Si_3N_4BN层状复合材料  

Fabrication of SiC Whisker Reinforced Laminated Si_3N_4 /BN Ceramics by Spark Plasma Sintering

作　　者：李翠伟[1] 黄勇[1] 汪长安[1] 汤珂[1] 李淑琴[1] 

机构地区：[1]清华大学材料科学与工程系新型陶瓷与精细工艺国家重点实验室,北京100084

出　　处：《无机材料学报》2002年第6期1220-1226,共7页Journal of Inorganic Materials

基　　金：国家自然科学基金(51072023)

摘　　要：采用放电等离子烧结技术(SPS)快速烧结了SiC晶须增强的Si3N4/BN层状复合材料.利用SPS技术,在烧结温度为1650℃、保温15min的条件下,材料的密度可达3.18g/cm3,抗弯强度高达600MPa,断裂功达到3500J/m2.研究表明:特殊的层状结构、SiC晶须的拔出与折断是材料断裂功提高的主要原因.X射线衍射及扫描电子显微镜研究表明:α-Si3N4已经在短短的烧结过程中全部转变成长柱状的β-Si3N4,并且长柱状的β-Si3N4和SiC晶须具有明显的织构.SiC whisker reinforced laminated Si3N4/BN ceramics with additives Y2O3, Al2O3 and MgO were prepared by spark plasma sintering(SPS) in 13min of heating to 1650degreesC and 15min dwell time. The density of the samples densified by SPS was 3.18g/cm(3). Bending strength reached 600 MPa, and the work of fracture reached 3500 J/m(2). The arrangement of hard Si3N4 layer and soft BN layer, the pull-out and broken of SiC whisker were the main reason for improving toughness of this ceramic. XRD and SEM indicated SiC whisker, long rod like beta-Si3N4 and platelet like hex-BN were the main phase and SiC whisker, long rod like beta-Si3N4 had strong preferred orientation.

关 键 词：SIC 晶须增强 Si3N4/BN层状复合材料 放电等离子烧结 氮化硅 氮化硼 陶瓷 

分 类 号：TB332[一般工业技术—材料科学与工程] TQ174.[化学工程—陶瓷工业]