Tensile strength of carbon

Depending upon the stress load, time, and temperature, the extension of a metal associated with creep finally ends in failure. Creep-rupture or stress-rupture are the terms used to indicate the stress level to produce failure in a material at a given temperature for a particular period of time. For example, the stress to produce rupture for carbon steel in 10,000 hours (1.14 years) at a temperature of900°F is substantially less than the ultimate tensile strength of the steel at the corresponding temperature. The tensile strength of carbon steel at 900°F is 54,000 psi, whereas the stress to cause rupture in 10,000 hours is only 11,500psi. 

The tensile strength of carbon nanotubes has been determined to be over 50 times that of high-carbon steel (Yu et al., 2000). The strength of the bond structure in carbon nanotubes... 

It is well known that the tensile strength of carbon black filled hydrocarbon rubbers increases with black structure at elevated temperatures, but not at room temperature or below (175). Since primary structure in carbon black increases modulus, hysteresis, and stress-softening (Section VII), an increase of the strength with structure might be expected on consideration of Eq. (32). The conditions under which tensile strength becomes independent of carbon black structure correspond to the regime... 

Fig. 9.13. Tensile strengths of carbon steels at various temperatures.

A.3.2 Factors affecting tensile strength of carbon fibers... 

Johnson JW, Factors affecting the tensile strength of carbon-graphite fibres. Applied Polymer Symposia, No. 9, 229-243, 1969. 

Figure 5.7 Tensile strength of carbon fiber monofilaments as function of fiber diameter. Source Reprinted with permission from Fitzer E, PAN-based carbon fibers-present state and trend of the technology from the viewpoint of possibilities and limits to influence and control the fiber properties by the process parameters, Carbon, 27(5), 621-645, 1989. Copyright 1999, Elsevier.

Table 5.11 The effect of gage length on the tensile strength of carbon fibers heat treated to 2500°C.

Figure 5.43 The tensile strength of carbon fibers as a function of the density of stabilized fibers from an AN/ MA precursor at stabilization temperatures of O 240°C A 255°C 270°C. Source Reprinted with permission from Takaku A, Hashimoto T, Miyoshi T, J AppI Polym Sci, 30, 1565, 1985. Copyright 1985, John Wiley Sons Ltd.

Figure 15.5 Ultimate tensile strength of carbon fiber reinforced cement. Source Reprinted from Aveston J, Mercer RA, Sillwood JM, Conference Proceedings Composites Standards Testing and Design, NPL 1974, IPC Science Technology Press, 93-103, 1974.

Manders PW, Kowalski IM, The effect of small angular fibre misalignments and tabbing techniques on the tensile strength of carbon fiber composites, 32nd International SAMPE Symposium, 985-996, Apr 6, 1987. 

Miwa M, Horiba N, Effects of fibre length on tensile-strength of carbon glass-fibre hybrid composites, J Mater Sci, 29(4), 973-977, 1994. 

FIG. 11 Tensile strength of carbon fAres as a function of thickness of the plasmapolymer layer. Parameters see in FIG. 10... 

If we perform a similar analysis with respect to the tensile strength of carbon fibers, we can write ... 

Xiao and co-workers [79] found that the Young s Modulus and tensile strength of carbon nanofibre reinforced LDPE increased by 89 and 56%, respectively, with incorporation of CNT. 

Tensile Strength of Carbon- and Glass-Reinforced Engineering Thermoplastics... 

Table 9.9. Tensile Strength of Carbon Fiber, SiC- and B4C-Matrix Composites...

The disposition of boundaries between the fiber types is somewhat arbitrary. For carbon fibers type HT, the values of the strength-to-stiffitess ratio are typically larger than 1.5-10-2, The tensile strength of carbon fibers is flaw controlled, however, and therefore the measured values increase strongly as the diameter of the filaments is decreased. 

Tran, C.D., Humphries, W., Smith, S.M., Huynh, C., Lucas, S., 2009. Improving the tensile strength of carbon nanotube spun yams using a modified spinning process. Carbon 47, 2662-2670. 

Hartley and Parfitt (1984) improved the split cell tensile strength apparatus by separation of the split cell of Ashton et al. (1964) to allow higher packing densities. The rack-and-pinion application was also replaced by a vibration-free variable speed mechanism. This was a vast improvement over the Ashton et al. s original apparatus and that of the pulley and string mechanism of Yokoyama et al. (1982). This improved instrument thus allowed the tensile strength of carbon blacks to be measured to an accuracy of better than 0.1%. The apparatus once again consisted of three basic sections a split cell and clamp, a compaction unit and a base unit with means to separate the split cell and measure the tensile stress as a function of time. 

Figure 5.8 Relation between tensile modulus and transverse tensile strength of carbon fibre composites.

The mechanical properties are changed by water absorption and as a consequence of photo-oxidative degradation. In actual practice, the mechanical properties are often maintained for years, even if the parts are severely weathered optically. Table 5.9 shows the reduction in tensile strength of carbon-black stabilized polyamides after twelve years exposure to various climate zones [14]. 

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