Carbon fibers microstructure

L. E. Jones and P. A. Thrower, Influence of boron on carbon fiber microstructure, physical properties and oxidation behavior, Carbon, 29[2], 251-269 (1991). 

Podkopaev SA, Tyumentsev VA, Yagafarov SS, Saunina SI, Influence of heat-treatment conditions on carbon-fiber microstructure, Russian J Appl Chem, 67(3), Pt 1, 385-387, 1994. 

Figure 5.3 Representations of different carbon fiber microstructures.

Fig. 9.1 Top view on two variants of C3 materials. The carbon fibers (a) themselves exhibit a complex inner microstructure that needs carful optimization for strength and stability. The isotropic filler phase (b) should be free of pores and other weak points caused by uneven distribution in the composite body. The ordered graphitic BSU (c) can provide a very strong but still flexible anchoring of the fibers in the isotropic matrix.

Of the most common DL materials, carbon fiber papers are widely known for being mechanically weak because their microstructure is destroyed when excessive compression forces are applied to them (i.e., when compressing a fuel cell). This destruction of the materials affects the porosity, which has a... 

Carbon fibers Polished Small size, possibly very small volume Variable carbon microstructure Important for in vivo use lb,2... 

Microstructure Formation in Mesophase Carbon Fibers and Other Graphitic Materials... 

This paper commences with evidence for lamelliform morphologies in mesophase carbon fiber, summarizes relevant information on disclination structures in the carbonaceous mesophase, and then reviews what we learn of disclination behavior from hot-stage observations and from deformation and carbonization experiments. The results indicate that disclination interactions that occur before the mesophase is fully hardened play an important role in determining the microstructures of mesophase carbon fibers, as well as those of cokes and graphites that form through the carbonaceous mesophase. 

Microstructure of non-woven mats of (a) glass and (b) carbon fibers. 

In recent years, activated carbons fibers (ACFs) because of their high surface area, microporous character, and the chemical nature of their surface have been considered potential adsorbents for the removal of heavy metals from industrial wastewater [1 3]. The properties of ACFs are determined by their microstructure, it is therefore important to investigate the microstructure of ACFs in terms of specific surface area, micropore volume, pore size distributions, surface chemistry and so on. Also, the adsorption properties of carbonaceous adsorbents are dependent on not only the porous structure but also the surface chemistry [3,4]. 

Z. Ryu, H. Rong, J. eng, M. Wang, and B. Zhang, Microstructure and chemical analysis of PAN-based activated carbon fibers prepared by different activation methods. Carbon 40 (2002) pp. 1144-1147. 

FIGURE 12.11 Improvements of the mechanical properties of three-dimensional reinforced CMCs by hybrid infiltration routes (a) R.T. flexural stress-strain plots for a three-dimensional carbon fiber reinforced composite before and after cycles of infiltration (comparison between eight cycles with zirconium propoxide and fonr cycles pins a last infiltration with aluminum-silicon ester (b) plot of the mechanical strength as a fnnction of the final open porosity for composites and matrix of equivalent porosity, before and after infiltration (Reprinted from Colomban, R and Wey, M., Sol-gel control of the matrix net-shape sintering in 3D reinforced ceramic matrix composites, J. Eur. Ceram. Soc., 17, 1475, 1997. With permission from Elsevier) (c) R.T. tensile behavior (d) comparison of the R.T. mechanical strength after thermal treatments at various temperatures. (Reprinted from Colomban, R, Tailoring of the nano/microstructure of heterogeneous ceramics by sol-gel routes, Ceram. Trans., 95, 243, 1998. With permission from The American Ceramic Society.)... 

The production of carbon fibers or filaments by decomposing a hydrocarbon gas over a transition metal catalyst has been the subject of extensive research. The product consists of filaments with diameters in the range of 1-100 pm and lengths up to 100 mm. In microstructure, it is different from traditional carbon fibers, resulting in a sword and sheath fracture mode without catastrophic failure. Since, in addition, these fibers are produced in a single step with no really expensive processing, they are attractive candidates for reinforcing composites. 

Mochida, I., Yoon, S.-H., Takano, N., et al. (1996). Microstructure of mesophase pitch-based carbon fiber and its control. Carbon, 34, 941-56. 

Lu, A.H. and Zheng, J.T. (2001). Study of microstructure of high surface area polyacrylonitrile activated carbon fibers./ Colloid Interface Sci., 236, 369-74. 

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