Epoxy matrix composites

Using a method suggested by Saint-Flour and Papirer [100], Schultz and Lavielle obtained A// -values for the interaction of several vapors of differing donor numbers and acceptor numbers with various treated and untreated carbon fibers used in the preparation of carbon fiber-epoxy matrix composites. was expressed as ... 

Fig. 2.5. Modulus data as a function of distance from the fiber surface of a carbon fiber-epoxy matrix composite which are measured from nanoindentation experiments. After Williams et al. (1990).

Fig. 2.7. Spectra of a glass fiber-epoxy matrix composite (a) before and (b) after hydrolysis. After Liao...

Fig. 3,4. Ln-Ln plot of fiber fragment length as a function of fiber stress (a) for Kevlar 29 fiber-epoxy matrix composite and (b) for a carbon fiber-epoxy matrix composite. Yabin et al. (1991).

Sandorf, 1980 Whitney, 1985 Whitney and Browning, 1985). According to the classical beam theory, the shear stress distribution along the thickness of the specimen is a parabolic function that is symmetrical about the neutral axis where it is at its maximum and decreases toward zero at the compressive and tensile faces. In reality, however, the stress field is dominated by the stress concentration near the loading nose, which completely destroys the parabolic shear distribution used to calculate the apparent ILSS, as illustrated in Fig 3.18. The stress concentration is even more pronounced with a smaller radius of the loading nose (Cui and Wisnom, 1992) and for non-linear materials displaying substantial plastic deformation, such as Kevlar fiber-epoxy matrix composites (Davidovitz et al., 1984 Fisher et al., 1986), which require an elasto-plastic analysis (Fisher and Marom, 1984) to interpret the experimental results properly. 

Fig. 3.27. Effect of the interface shear strength on mechanical properties of carbon fiber-epoxy matrix composites ( ) tran.sverse tensile strength (A) maximum transverse tensile strain (O) transverse tensile modiilns. After Madhukar and Drzal (1991),...

Interface properties of carbon fiber-epoxy matrix composites and Weibull parameters of carbon fibers"... 

Fig. 4.8. Variations of debond length, t, as a function of applied stress, for different coefficients of friction, p, for a XAIOO carbon fiber-epoxy matrix composite. After Zhou et al. (1995a, b).

Fig. 4.23. Plot of parlial debond stress, as a function of debond length, (. for a carbon fiber-epoxy matrix composite. After Kim ct al, (1992).

Fig. 4.26. Comparisons between experiments and theory of (a) maximum debond stress, trj, and (b) initial frictional pull-out stress for carbon fiber-epoxy matrix composites. After Kim et al. (1992).

Fig. 4,40. Distributions of interface shear stress, r, along the fiber length at a constant applied stress o = 4.0GPa for carbon fiber-epoxy matrix composites in fiber pull-out and fiber push-out. After...

Fig. 5.7. Effect of immersion in hot water on interfacial bond strength of silane treated glass fiber-epoxy matrix composite. After Koenig and Emadipotir (1985).

Fig. 5.17. Comparison between the compressive and tensile (a) strengths and (b) moduli of carbon fiber-epoxy matrix composites with three types of fiber surface condition. AU-4 without surface treatment AS-4 with surface treatment AS-4C with coating of pure epoxy after surface treatment. After Drzal and...

Summary of olT-axis properties of carbon fiber-828 mPDA epoxy matrix composites with different fiber surface treatments"... 

Fig. 5.18. Comparison of shear strengths of carbon fiber-epoxy matrix composites determined from three dificrcnt test methods. Fiber surface conditions as in Fig. 5.17. After Drzal and Madhukar (1993).

Fig. 5.21. Surface amine concenlralion (O) of aramid fiber and ILSS ( ) of epoxy matrix composites as a function of ammonia plasma treatment time. After Brown et al. (1991).

Fig. 7,2. Fracture toughness, R, of Kevlar 49-epoxy matrix composites (a) under varying strain rates in three-point bending and (b) at different temperatures under impact loading (O) uncoated fibers (0)41%, (Q) 63% and ( ) 100% Estapol coated fibers (A) silicone vacuum fluid (SVF) coated fibers. After Mai...

Fig. 7.4. Fracture toughness (O) and flexural strength ( ) of silicone rubber coated carbon fiber-epoxy matrix composites as a function of coating thickness. After Hancox and Wells (1977).

Fig. 7.5. (a) Transverse impact fracture toughness and (b) fiber pull-out length versus testing temperature for carbon fiber-epoxy matrix composites with and without PVAL coatings on fibers. After Kim and... 

Fig, 7.7. Scanning electron microphotographs of fracture surfaces for earbon fiber epoxy matrix composites (a) anil (b) without PVAL coatings (c) and (d) with PVAL coatings on libers. After Kim et al,... 

Fig. 7.8. (a) Normalized impact fracture toughness and (b) interlaminar shear strength (ILSS) of carbon fiber-epoxy matrix composites as a function of glycidyl acrylate/methyl acrylate (GA/MA) interlayer... 

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