通过单向拉伸试验,对比研究平纹编织C/SiC陶瓷基复合材料在室温和高温(1300℃,包括惰性气氛和湿氧气氛)环境下的宏观力学特性,并采用光学显微镜和扫描电镜对试件断口进行显微观察,分析其损伤模式和破坏机理.结果表明: C/SiC复合材料的室温和高温拉伸行为通常表现为非线性特征,在低应力时就开始出现损伤;纤维与基体之间界面滑行阻力的降低使C/SiC复合材料在高温惰性气氛环境下的拉伸强度和破坏应变均比室温下的高;碳纤维的氧化严重影响材料的承载能力导致高温湿氧环境下的拉伸强度和破坏应变均比室温下的低; C/SiC复合材料室温和高温下的拉伸均呈现韧性断裂,断口较为相似,只是纤维拔出长度和断口的平齐程度有所不同,其中高温惰性气氛环境下纤维拔出最长,高温湿氧环境下试件断口有明显的被氧化痕迹;0°纤维束表面基体开裂、明显的层间分层以及0°纤维和纤维束的拔出和断裂同时携带90°纤维束拔出是C/SiC复合材料在室温和高温下的拉伸破坏机理.
Monotonic tensile experiments at room temperature and 1300℃ were performed to investigate the macro-mechanical behavior of plain-woven C/SiC ceramic matrix composites(CMCs) produced with CVI technique.Two environments including inert atmosphere and wet oxygen atmosphere were simulated at 1300℃.The microstructure of specimens were observed by optical microscope and scanning electron microscope to analyse its damage mechanism.The results indicate that, the responses of C/SiC composite under tensile loading at both room temperature and 1300℃ are nonlinear to rupture and damage appears at very low stress level. The tensile strength and failure strain at room temperature are lower than at 1300℃ in inert atmosphere but higher than at 1300℃ in wet oxygen atmosphere, respectively.The main reason of the former is the decrease of interfacial sliding resistance at 1300℃ in inert atmosphere.The main reason of the latter is fiber oxidation at 1300℃ in wet oxygen atmosphere. The tensile specimens all break in a ductile manner. Fractography analysis shows that the fracture surfaces are almost the same in the three environments except the obviously oxidative trace in wet oxygen atmosphere .The specimens in inert atmosphere have the longest pull-out length of fiber. Matrix cracks around the 0° fiber bundles, interlaminar cracks , fracture and pullout of 0° fiber and 0° bundles along with the pullout of 90°bundles are the main damage mechanisms.
参考文献
[1] | 张立同,成来飞,徐永东.新型碳化硅陶瓷基复合材料的研究进展[J].航空制造技术,2003(01):24-32. |
[2] | Torben K.Jacobsen;Povl Brondsted .Mechanical Properties of Two Plain-Woven Chemical Vapor Infiltrated Silicon Carbide-Matrix Composites[J].Journal of the American Ceramic Society,2001(5):1043-1051. |
[3] | CALARD V;LAMON J .A probabilistic-statistical approach to the ultimate failure of ceramic-matrix composites.Part Ⅰ:experimental investigation of 2D woven SiC/SiC composites[J].Composites Science and Technology,2002,62:385-392. |
[4] | DALMAZ A;DUCRET D;GUERJOUMA R et al.elastic module of a 2.5D Cf/SiC composite:experimental and theoretical estimates[J].Composites Science and Technology,2000,60:913-925. |
[5] | Camus G. .Modelling of the mechanical behavior and damage processes of fibrous ceramic matrix composites: application to a 2-D SiC/SiC[J].International Journal of Solids and Structures,2000(6):919-942. |
[6] | J.L. Chaboche;J.F. Maire .New progress in micromechanics-based CDM models and their application to CMCs[J].Composites science and technology,2001(15):2239-2246. |
[7] | CAMUS G;GUILLAUMAT L;BASTE S .Development of damage in a 2D woven C/SiC composite under mechanical loading Ⅰ:mechanical characterization[J].Composites Science and Technology,1996,56:1363-1372. |
[8] | 王波,矫桂琼,潘文革,陶亮.三维编织C/SiC复合材料的拉压实验研究[J].复合材料学报,2004(03):110-114. |
[9] | 王波,矫桂琼.三维编织C/SiC复合材料剪切和弯曲性能的实验研究[J].机械强度,2007(01):44-47. |
[10] | 杜双明,乔生儒,纪岗昌,韩栋.3D-C/SiC复合材料在室温和1300℃的拉-拉疲劳行为[J].材料工程,2002(09):22-25. |
[11] | 潘文革,矫桂琼,王波,管国阳.声发射技术在三维编织C/SiC复合材料拉伸损伤分析中的应用[J].无机材料学报,2004(04):871-875. |
[12] | 乔生儒,杨忠学,韩栋,李玫.3D-C/SiC复合材料拉伸蠕变损伤和蠕变机理[J].材料工程,2004(04):34-36. |
[13] | 任伟华,乔生儒,敖强.3D-C/SiC复合材料热震损伤行为[J].材料工程,2003(12):26-28. |
[14] | 管国阳,矫桂琼,张增光.2D-C/SiC复合材料的宏观拉压特性和失效模式[J].复合材料学报,2005(04):81-85. |
[15] | 潘文革,矫桂琼,管国阳.二维机织碳纤维/碳化硅陶瓷基复合材料损伤分析[J].硅酸盐学报,2005(11):1321-1325. |
[16] | 管国阳,矫桂琼,张增光,潘文革.平纹编织C/SiC复合材料的失效判据[J].硅酸盐学报,2005(09):1100-1104. |
[17] | 孙龙生,姚磊江,吕国志,童小燕.二维平纹编织CVI工艺C/SiC复合材料的疲劳行为[J].西北工业大学学报,2007(04):478-481. |
[18] | 管国阳,矫桂琼,张增光.平纹编织C/SiC复合材料的剪切性能[J].机械科学与技术,2005(05):515-517. |
[19] | CHAWLA K.Ceramic Matrix Composite[M].USA:Kluwer Academic Publisher,2003:298-301. |
[20] | EVANS A;DOMERGUE J;VAGAGINI E .Methodology for relating the tensile constitutive behavior of ceramic-matrix composites to constituent properties[J].Journal of the American Ceramic Society,1994,77:1425-1435. |
[21] | Yongdong Xu;Laifei Cheng;Litong Zhang .Microstructure and Mechanical Properties of Three-Dimensional Textile Hi-Nicalon SiC/SiC Composites by Chemical Vapor Infiltration[J].Journal of the American Ceramic Society,2002(5):1217-1221. |
[22] | VAGAGINI E;DOMERGUE J;EVANS A .Relationships between hysteresis measurements and the constituent properties of ceramic matrix composites:I,theory[J].Journal of the American Ceramic Society,1995,78(10):2709-2720. |
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