The relationship between the mechanical properties and microstructures of carbon fibers
-
摘要: 炭纤维具有复杂的微观结构，使得不同炭纤维的微观结构和力学性能之间存在差异，特别是相近性能炭纤维之间的差异甚是微妙。本文采用万能材料试验机、X射线衍射、小角散射和拉曼光谱对炭纤维单丝样品进行了力学性能和微观结构的表征。结果表明，除SY300外，相近性能炭纤维的拉伸强度随d002和R的减小而增大，随Lc的增大而增大；对于同种原丝生产工艺的炭纤维，拉伸强度随微孔半径和密度的减小而增大。拉伸强度的离散可用Weibull模数进行表征，随微孔半径的减小而降低。根据实验数据采用Griffith（Irwin）公式估算得到的炭纤维拉伸强度比实测强度大，采用Mathematics和MATLAB软件对拉伸强度和微观结构数据进行了数值模拟，得到拉伸强度的估算公式，经采用其它研究者给出的T300炭纤维微观结构数据验证对比，得到的拉伸强度数据与测试数据相符。Abstract: Differences in the microstructure of carbon fibers are subtle for carbon fibers with similar mechanical properties. The mechanical properties and microstructures of six carbon fibers were investigated by a universal material testing machine, X-ray diffraction, small angle X-ray scattering and Raman spectroscopy to reveal the relationship between the tensile strengths of carbon fibers and their microstructures. Results indicate that the tensile strength increases with decreasing d002 or ID/IG values, and increases with increasing Lc for five of the six carbon fibers examined. Differences in the tensile strength were characterized by a Weibull modulus increase with increasing micropore radius. The Griffith theory over-estimates the tensile strength of the six carbon fibers. A more accurate formula is proposed to correlate the tensile strength with the microstructures of carbon fibers based on both the Griffith and Weibull theories, which takes into account the tensile strength loss due to the three-layer structure of carbon fibers (an inner-surface layer, an outer-surface layer and a core), defects and the tensile strength of carbon fibers, and is validated by the experimental data on T300 carbon fibers from other researchers.
-
Key words:
- Carbon fiber /
- XRD /
- Weibull /
- Element /
- Microstructure
-
Tsai S W, Wu E W. A general theory of strength for anisotropic materials[J]. Journal of Composite Materials, 1971, 5:58-80. Harlow D G, Phoenix S L. Bounds on the probability of failure of composites[J]. International Journal of Fracture, 1979, 15(4):321-336. Jamal E, Franclois T, Raymond G. Review of failure criteria of fibrous composite materials[J]. Polymer Composites, 1996, 56(6):183-196. Griffith A A. The phenomena of rupture and flow in solids[J]. Philosophical Transactions of the Royal Society of London, 1920, 211:163-198. Peirce F T. Tensile tests for cotton yarns, "The weakest link" Theorems on the strength of long and of composite specimens[J]. Journal of the Textile Institute, 1926, 17(7):355-368. Weibull W. A statistical theory of the strength of materials[J]. The Royal Swedish Institute for Engineering Research Preceeding, 1939, 151:1-45. Fu H. Carbon Fiber and Graphite Fiber[M]. Chemical Industry Press, 2010:369. Fujie L, Haojing W, Linbing X, et al. Effect of microstructure on the mechanical properties of PAN-based carbon fihers during high-temperature graphitization[J]. Journal of Materials Science, 2008, (43):4316-4322. Cédric S, Jacques L, René P. The tensile behavior of carbon fibers at high temperatures up to 2400℃[J]. Carbon, 2004, 42(4):715-725. Ogalev A A, Lin C, Anderson D P, et al. Orientation and dimensional changes in mesophase pitch-based carbon fibers[J]. Carbon, 2002, 40(8):1309-1319. Guinier A, Foumet G. Small-angle scattering of X-rays[C]. New York:Wiely, 1955:17-65. Bale H D, Schmidt P W. Small-angle X-ray-scattering investigation of submicroscopic porosity with fractal properties[J]. Physical Review letters, 1984, 53(53):596-599. Tuinstra F, Koening J L. Raman spectrum of graphite[J]. Journal of Chemical Physics, 1970, 53(3):1126-1130. Weidong Y. Jiangwei Y. Tensile strength and its variation of PAN-based carbon fibers. I. Statistical distribution and volume dependence[J]. Journal of Applied Polymer Science, 2007, 101(5):3175-3182. Natio K. Tensile properties and Weibull modulus of some high-performance polymeric fibers[J]. Journal of Applied Polymer Science, 2013, 128(2):1185-1192. Natio K, Yang J, Tanaka Y, et al. The effect of gauge length on tensile strength and weibull modulus of polyacrylonitrile (PAN)-and pitch-based carbon fibers[J]. Journal of Material Science, 2012, 47:632-642. Johnson D J, Tyson C N. Low-angle X-ray diffraction and physical properties of carbon fibres[J]. Journal of Physics d-applied Physics, 1970, 3:526. Kobayashi T, Sumiya K, Fukuba Y, et al. Structure heterogeneity and stress distribution in carbon fiber monifilament as revealed by synchrotron microbeam X-ray scattering and micro-Raman spectral measurements[J]. Carbon, 2011, 49:1646-1652. Johnson D J. Structure-property relationships in carbon fibers[J]. Journal of Physics applied Physics, 1987, 20:287. Moreton R, Watt W, Johnson W. Carbon fibres of high strength and high breaking strain[J]. Nature, 1967, 213:690-691. Cooper G A, Mayer R M. The strength of carbon fibres[J]. Journal of Material Science, 1971, 6:60-67. Honjo K. Fracture toughness of PAN-based carbon fibers estimates from strength-mirror size relation[J]. Carbon, 41(5):979-984. Bansal G K. Effect of flaw shape on strength of ceramics[J]. Journal of the American Ceramic Society,1976,59(1/2):87-88. Wenfeng B, Shuxiang L, Qingtian L. Micro compound method of elasticity coefficient of carbon fiber[J]. Acta Material Composite Sinica, 2012, 29(1):212-215. Chen W, Mengfan W, Daxin L, et al. Relationship between the density and graphite structure of carbon fiber during high temperature treatment process[J]. Journal of Materials Science and Engineering, 2013, 31(6):803-806. Kuniaki H. Fracture toughness of PAN-based carbon fibers estimated from strength-mirror size relation[J]. Carbon, 2003, 41(5):979-984. Zetian C. Studies on the structure and micro-mechnical properties of carbon fiber by Raman spectrum[D]. Shanghai:Dong Hua University, 2011. Dongfeng L, Haojing W, Fu H. Structure and properties of T300 and T700 carbon fibers[J]. New Carbon Matericals, 2007, 22(1):59-64. Yi S, Caihong Z, Yao X, et al. Investigation of PAN-based carbon fiber microstructure by 2D-SAXS[J]. New Carbon Matericals, 2009, 24(3):270-276. -
下载:
点击查看大图
图(1)
计量
- 文章访问数: 351
- HTML全文浏览量: 124
- PDF下载量: 99
- 被引次数: 0
