纤维丝束大小对Mini-C/SiC拉伸性能与强度分布的影响  

Influence of Fiber Bundle Size on Tensile Properties and Strength Distribution of Mini-C/SiC

作　　者：孟志新 罗磊[3] 陈婧旖 李斌 李敏 张毅 成来飞 MENG Zhi-xin;LUO Lei;CHEN Jing-yi;LI Bin;LI Min;ZHANG Yi;CHENG Lai-fei(School of Material Engineering,Xi'an Aeronautical University,Xi'an 710077,China;Key Laboratory of Ultra-High Temperature Structural Composite Materials,Northwest Polytechnic University,Xi'an 710072,China;Beijing Institute of Space Long March Vehicle,Beijing 100076,China;The Sixth Military Representative Office of the Rocket Force Equipment Department in Xi'an,Xi'an 710072,China;Aviation Electromechanical Equipment Maintenance Department,Changsha Aeronautical Vocational and Technical College,Changsha 410000,China)

机构地区：[1]西安航空学院材料工程学院,西安710077 [2]西北工业大学超高温结构复合材料重点实验室,西安710072 [3]北京航天长征飞行器研究所,北京100076 [4]火箭军装备部驻西安地区第六军事代表室,西安710072 [5]长沙航空职业技术学院航空机电设备维修学院,长沙410000

出　　处：《当代化工》2021年第8期1810-1813,1871,共5页Contemporary Chemical Industry

基　　金：国家自然科学青年基金(项目编号:51802263);湖南省自然科学基金科教联合基金(项目编号:2017JJ5057);西安航空学院科研基金(项目编号:2017KY0205)。

摘　　要：为了探究碳纤维丝束大小对纤维束复合材料碳/碳化硅(Mini-C/SiC)拉伸性能和强度分布的影响,采用化学气相浸渗(CVI)法制备了1k Mini-C/SiC和3k Mini-C/SiC复合材料。测试了C纤维束以及Mini-C/SiC复合材料的拉伸性能,并采用两参数Weibull分布模型分析了强度分布,同时还观察了拉伸断口形貌。结果表明:3k C纤维束表现出了明显的"聚拢效应",其拉伸性能和强度稳定性均优于1k C纤维束,而且其拉伸强度、Weibull模数、特征强度、延伸率和断裂功分别比1k C纤维束的高47%、13%、46%、54%和102%。同时,1k C纤维束发生韧性断裂,3k C纤维束发生脆性断裂。3k Mini-C/SiC复合材料的拉伸性能和强度稳定性均优于1k Mini-C/SiC复合材料,其拉伸强度、Weibull模数、特征强度、延伸率和断裂功分别比1k Mini-C/SiC复合材料提高了67%、69%、63%、92%和216%,而且两者的拉伸断裂方式均为典型的脆性断裂。纤维体积分数高是大纤维丝束复合材料3k Mini-C/SiC拉伸性能和强度稳定性优于小纤维丝束复合材料1k Mini-C/SiC的主要原因。In order to explore the influence of fiber bundle size on the tensile properties and strength distribution of fiber bundle composites carbon/silicon carbide(Mini-C/SiC), 1 k Mini-C/SiC and 3 k Mini-C/SiC composites were fabricated by chemical vapor infiltration(CVI). The tensile properties of carbon fiber bundles and Mini-C/SiC composites were tested, and the two-parameter Weibull distribution model was used to analyze the strength distribution. At the same time, the tensile fracture morphologies were observed. The experimental results showed that the 3 k carbon fiber bundle exhibited obvious “gathering effect”, its tensile properties and strength stability were better than those of 1 k carbon fiber bundle, and its tensile strength, Weibull modulus, characteristic strength, elongation and fracture work were 47%, 13%, 46%, 54% and 102% higher than those of 1 k carbon fiber bundle, respectively. Meanwhile, 1 k carbon fiber bundle underwent ductile fracture, and 3 k carbon fiber bundle underwent brittle fracture. The tensile properties and strength stability of 3 k Mini-C/SiC composite were better than those of 1 k Mini-C/SiC composite. The tensile strength, Weibull modulus, characteristic strength, elongation and fracture work of 3 k Mini-C/SiC composite were 67%, 69%, 63%, 92% and 216% higher than those of 1 k Mini-C/SiC composite, respectively. In the meantime, their tensile fracture modes were typical brittle fracture. The higher fiber volume fraction was the main reason why the tensile properties and strength stability of 3 k Mini-C/SiC composite with larger fiber bundle were better than those of 1 k Mini-C/SiC composite with smaller fiber bundle.

关 键 词：陶瓷基复合材料 Mini-C/SiC 碳纤维丝束 拉伸性能 强度分布 

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]