Carbon fiber polymer matrix composite CFRP

In using Eq. (6.10) to predict / , of a given composite system it is important that the said failure mechanisms all exist. If any one mechanism is apparently absent the corresponding toughness term must be excluded from the / t equation. It is also worth emphasizing that / , varies linearly with reciprocal of the frictional shear strength of the interface, i.e. l/tf, with the lower limit of (1 — Ff)/fm when if approaches infinity. This relationship has been shown to apply to many carbon fiber polymer matrix composites (CFRPs) (Harris et al., 1971 Beaumont and Phillips,... 

Fig. 7.24. Predicted fracture toughness of carbon and glass fiber-polymer matrix composites (CFRP and GFRP) with varying matrix shrinkage stress, n. After Piggott (1981).

Fitzer, E. (1985). Technical status and future prospects of carbon fibers and their application in composites with polymer matrix (CFRPs), pp. 3-45. In Fitzer, E. Ed. Carbon Fibers and Their Composites. Springer-Verlag, New York. 

Carbon nanotubes can be used in reinforcing polymer matrix composites in two ways a) as the sole reinforcing phase (CNTRP), or b) as an additional reinforcing phase in conjunction with carbon fibers (CF+CNT) in a hybrid composite. Carbon nanotubes reinforced plastics (CNTRP) can be prepared by several methods, as described in section 15.1.3. Both CFRP and CNTRP composite structures can be joined using structural adhesives but machining and drilling are difficult as a result of the widely different properties of their constituents. 

Denison P, Jones FR, Brown A, Humphrey P, Paul AJ, Scanning SIMS spectography of cfrp, Ishida H ed., Interfaces in Polymer, Geramic and Metal Matrix Gomposites, 239-248, 1988. Hearn MJ, Briggs D, ToF-SIMS studies of carbon fiber surfaces and carbon fiber composite fracture surfaces. Surface Interface Analysis, 17(7), 421 et seq, 1991. 

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