短切碳纤维增强碳化硅陶瓷基复合材料的高温冲击压缩力学性能  

Mechanical Property of Short Carbon Fiber-reinforced SiC Ceramic Matrix Composites in High Temperature Shock Compression

作　　者：徐颖[1,2] 郑志涛[1] 许维伟[1] 袁璞[1] 邵彬彬 

机构地区：[1]安徽理工大学土木建筑学院,淮南232001 [2]煤矿深井建设技术国家工程试验室(淮北),淮北235000

出　　处：《材料导报》2016年第14期98-103,共6页Materials Reports

基　　金：高等学校博士学科点专项科研基金项目(20123415110001)

摘　　要：采用先驱体浸渍裂解法(即PIP法)制备出3种不同短切碳纤维(C_(sf))体积分数的圆柱形短切碳纤维增强陶瓷基复合材料(C_(sf)/SiC复合材料)试件,通过高温加热装置和自组装功能的霍普金森压杆装置对试件进行高温和动态荷载耦合作用下的冲击压缩试验,并通过扫描电子显微镜(SEM)观察C_(sf)/SiC复合材料断口形貌,对试件的破坏形态进行分析。试验结果表明,采用PIP法制备的C_(sf)/SiC复合材料试件中C_(sf)分布均匀,在外应力作用下C_(sf)/SiC复合材料试件发生破坏,碳纤维和碳纤维束与SiC基体脱粘被不断拔出。试件的抗压强度随C_(sf)体积含量的增加而呈现先增加后减小的变化趋势,C_(sf)体积含量为21%的试件抗压强度最高,为96.55 MPa。与常温相比,在高温压缩试验中随着复合材料试件平均温度的升高,C_(sf)/SiC复合材料试件破碎后的块度越来越大,整体性越来越好,当温度达到300℃时,C_(sf)体积含量对C_(sf)/SiC复合材料试件抗压强度的影响较小。Three kinds of short carbon fiber reinforced ceramic matrix composites （Csf/SiC composites） cylindrical specimens with different volume fraction of short carbon fiber （Csf） were prepared by precursor infiltration and pyrolysis （PIP）. Impact compression test was carried out by the high temperature heating device and Hopkinson pressure bar with self assembling function, and the specimens were subjected to high temperature and dynamic load in the test. The fracture morphology of Csf/SiC composites was observed by scanning electron microscopy （SEM）, and the failure patterns of the specimens were analyzed. The results showed that Csf was well-distributed in the Csf/SiC composites prepared by PIP method. Under the action of external stress, carbon fiber and carbon fiber bundles were pulled out as they were separated from the SiC matrix, which made the Csf/SiC composites specimens destroyed. With the increase of Csf volume, the compressive strength of the specimen increased first and then decreased. The specimens with 21% volume content of Csf presented the highest compressive strength of 96.55 MPa. In high temperature compression test, with the increase of the average temperature of composite materials, the block size of Ca/SiC composite specimen after broken became larger and larger, and the integrity became better and better. The content of Csf had little effect on the compressive strength of Csf/SiC composite at 300 ℃.

关 键 词：短切碳纤维 单轴压缩 高温 冲击荷载 分离式Hopkinson压杆(SHPB) 

分 类 号：TH212[机械工程—机械制造及自动化] TH213.3