烧结工艺对C_F/SiC层状复合材料断裂行为的影响  

Influence of Sintering Process on the Fracture Behavior of C_F/SiC Laminated Ceramic Composites

作　　者：孙万昌[1,2] 汪长安[2] 黄勇[2] 

机构地区：[1]西安科技大学,陕西西安710054 [2]清华大学 新型陶瓷与精细工艺国家重点实验室,北京100084

出　　处：《稀有金属材料与工程》2013年第S1期301-304,共4页Rare Metal Materials and Engineering

基　　金：国家自然科学基金项目(50172023);陕西省教育厅专项科研计划项目(11JK0824);榆林市产学研科技计划项目

摘　　要：采用碳纤维二维针织布片与SiC轧膜素坯片交替叠层,通过排胶和热压烧结工艺,成功地制备出CF/SiC层状复合材料,研究了烧结助剂体系、烧结温度及保温时间等烧结工艺对CF/SiC层状复合材料断口形貌及断裂行为的影响。结果表明:选择Al2O3、Y2O3及Si粉作为烧结助剂,烧结制度为1900℃/1.5h工艺条件下,材料易致密、不分层,CF/SiC层状复合材料的综合力学性能最佳;CF/SiC层状复合材料的主要增韧机制为裂纹在纤维布层内的多次横向偏转及纤维束与单根纤维的脱粘、断裂与拔出。CF/SiC laminated ceramic composites were prepared through rolling, stacking alternately 2D-carbon fiber cloth and SiC green layer, burning out of organic components and hot pressing. Sintering process parameters for fabricating CF/SiC laminated ceramic composites were investigated. The effects of sintering process parameters and sintering additives on the microstructure and fracture behavior of the laminated ceramics were analyzed. In addition, toughening mechanism for the laminated composites was discussed. The results indicate that, the laminated ceramics CF/SiC could be densified and possesses optimal mechanical properties, when sintered at 1900 ℃/1.5 h with Al2O3 , Y2O3 and Si sintering additives. The primary toughening mechanism for CF/SiC laminated ceramics could be mainly attributed to several crack deflection at the carbon fiber layer, fracture and pull out of carbon fiber bundles and carbon fiber within the carbon fiber layers.

关 键 词：层状陶瓷 CF/SIC 热压烧结 断裂行为 

分 类 号：TB332[一般工业技术—材料科学与工程] TF124.5[冶金工程—粉末冶金]