Composites Subject

Fig. 4. The performance of several grades of graphite and graphite composites subjected to thermal shock loading.

The transverse modulus, Ect, may be determined in a matmer similar to that described earlier for the longitudinal modulus. Consider a unidirectional fibre composite subjected to a transverse force, Fct, in the direction perpendicular to the fibre axis. 

Donald F. Adams, Inelastic Analysis of a Unidirectional Composite Subjected to Transverse Normal Loading, Journal of Corrposite Materials, July 1970, pp. 310-328. 

Birger, S., Moshonov, A. and Kenig, S. (1989). Failure mechanisms of graphite fabric epoxy composites subjected to flexural loading. Composites 20, 136-144. 

Shih, G.C. and Ebert, L.J. (1986). Interface strength effects on the compressive-flexure/shear failure mode transition of composites subjected to four-point bending. J. Mater. Sci. 21, 3957-3%5. 

Mitaka, Y. and Taya, M. (1985a). Stress field in a coated continuous fiber composite subjected to thermomechanical loadings. J. Composite Mater. 19, 554-578. 

Boyd, S., Compression Creep Rupture ofanE-Glass/Vinyl Ester Composite Subjected to Combined Mechanical and Fire Loading Conditions, Dissertation for Doctor of Philosophy in Engineering Mechanics, 2006. 

Figure 27. Flexural strength and bulk density of unidirectional composites subjected to graphitizing heat treatments either for each densification cycle or after the densification cycles were completed (20,52) The matrix was a coal-tar binder pitch with 10 wt.-% sulfur the high-modulus PAN-based fiber was Sigrafil HM.

Figure 5. Torsional shear properties of two 3D composites subjected to similar processing.

Fig. 5.5 Effect of changing the elastic modulus ratio and constituent creep stress exponents on the total strain rate of a 1-D composite subjected to tensile creep loading.31 In both (a) and (b), the dashed lines represent the composite behavior, and the thin solid lines the constituent behavior. In the calculations, it was assumed that the creep load was applied instantaneously.

Fig. 7.3 Examples of crack profiles in AI2O3/33 vol.% SiC whisker composite subjected to static and cyclic tensile loads (in a four-point bend configuration) in 1400°C air. From Ref. 22. Crack growth direction is from right to left, (a) Static crack growth at K 4-5 MPaVnT (b) Cyclic crack growth at R = 0.15 and vc = 0.1 Hz in the AK range 3.5-5 MPaVfiT...

Fig. 7.12 (a) A schematic representation of the pinning of grain boundaries by whiskers, (b) An example of the process shown in (a) in the fatigue crack tip region of the alumina/SiC composite subjected to fatigue fracture at 1400°C. From Ref. 61. A refers to alumina grains. 

S. Jannson and F. A. Leckie, Mechanical Behavior of a Continuous Fiber-Reinforced Aluminum Matrix Composite Subjected to Transverse and Thermal Loading, Journal of the Mechanics and. Physics of Solids, 40, 593-612 (1992). 

When data are isothermal, or isobaric over only a narrow range of temperature, determination of van Laar constants is conducted in a straightforward manner. The most accurate procedure is a nonlinear regression to obtain the best fit to the data over the entire range of binary composition, subject to minimization of some objective function. A less accurate, but extremely rapid, hand-calculation procedure can be used when experimental data can be extrapolated to infinite dilution conditions. Modern experimental techniques are available for accurately and rapidly determining activity coefficients at infinite dilution. Applying (5-26) to the conditions x, = 0 and then x, = 0, we have... 

Since components and are compositions subject to the constraint that they have to sum to unity, we can rewrite the definition of Xas in terms of components 1 and 2 ... 

Figure 1 Micrograph (optical microscopy) showing breaking of airbon fibers, metal fibers, and matrix on a CFRP composite subject to a 5J impact.

Radford. D.. Ganchev. S.. Qaddoumi. N.. Beauregard. G.. and Zoughi. R. (1994). Millimeter wave nondestructive evaluation of glass fiber epoxy composites subjected to impact fatigue. Proc. of the SPIE. Advanced Microwave and Millimeter-Wave Detectors Conf.. Vol. 2275. 

Donaldson SL, Mall S. Delamination growth in graphite/epoxy composites subjected to cyclic mode III loading. J Reinf Plast Compos 1989 8 91-103. http //dx.doi.org/ 10.1177/073168448900800106. 

Tekalur SA, Shivakumar K, Shukla A. Mechanical behaviour and damage evolution in E-glass vinyl ester and carbon composites subjected to static and blast loads. Composites Part B 2008 39 57-65. 

Specimens which were not exposed to the liquids did not show any delaminations. The combination of fatigue and exposure to aggressive fluids produced delaminations in the upper layer of the composite subjected to tensile stress. In specimens immersed in methyl ethyl ketone, moreover, buckling occurred at the compressive side. 

SNR Pakalapati, F Gadala-Maria and R E White, Dynamic mechanical analysis of a unidirectional carbon fibre-thermoplastic composite subjected to anodic and cathodic currents , Polym Compos 1996 17(4) 620-626. 

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