Carbon peek

K. Fujihara, Z.-M. Huang, S. Ramakrishna, K. Satknanantham, and H. Hamada. Performance study of braided carbon/PEEK composite compression bone plates. Biomaterials, 24(15) 2661-2667, July 2(X)3. 

There are also TP equivalents, such as high performance carbon/PEEK tapes, in which continuous filament and matrix have been closely combined by a form of pultrusion process and require only placing in position (often by winding or layering) and heating, to fuse the TP matrix. Technology extending the principle to continuous filament and PP matrices is also available. 

For both dry and saturated conditions, the carbon/epoxy system performed best and the carbon/PEEK was the least resistant to damage. The damage resistance of the E-glass/epoxy and the carbon/PEEK immersed specimens decreased with immersion, whilst the Scotch Ply improved. The carbon/epoxy material was not affected by immersion. The topography of the damaged surfaces had a considerable influence on their subsequent erosion behaviour. 

Zhou and co-workers [27] used calcium carbonate as a reinforcing agent for sulfonated PEEK. The calcium carbonate particles were surface treated and the effect of this on the mechanical and thermal properties were determined. The modulus and yield stress of the composites increased with CaCOs particles loadings. This increase was attributed to the bonding between the particles and the PEEK matrix. DSC experiments showed that the particle content and surface properties influenced the Tg and the T of the composites. The Tg increased with the content of fillers while Tn, decreased. The treated fillers were found to give a better combination of properties, which indicated that the sulfonated PEEK played a constructive role in the calcium carbonate/PEEK composites. 

Hamada, H., Coppola, J.C., Maekawa, Z. and Sato, H. (1992) Comparison of energy absorption of carbon/epoxy and carbon/PEEK composite tubes. Composites, 23(4), 245-252. 

Astrom, B.T., Larsson, P.H., Hepola, P.J. and Pipes, R.B. (1994) Flexural properties of pultruded carbon/PEEK composites as a function of processing history. Composites, 25(8), 814-821. 

The flexural fatigue data for both resin composites show that carbon/ PEEK has a lower degradation rate than that of carbon/epoxy for UD. The data for three alignments are contrasted in Table 10.5. 

Carbon/epoxy is slightly better with cross-plied laminates (0/90°), than carbon/PEEK, but both have similar properties compared with angled-plied laminates ( 45°). 

Figure 10.27 Flexural fatigue data for carbon/PEEK and carbon/epoxy both for 0° laminates (Buggy and Dillon).

Fujihara K, Huang ZM, Ramakrishna S et al (2cio4) Feasibility of knitted carbon/PEEK composites for orthopedic bone plates. Biomaterials 25 3877—3885... 

This improvement in performance in the bonded joint was attributed to tbe polarity of the composite surface. The intensity of corona treatment required to achieve the necessary degree of polarity was found to be dependent on tbe cure characteristics of the adhesive used and, to a certain extent, on the chemistry of the matrix. Thus, for the EA 9309, carbon/PEEK composites needed > 10 J/m and carbon-polyamide composites required a corona energy of > 3 J/mm. When FM-73M was used, the figures were > 20 J/mm and > 6 J/mm, respectively — i.e. double the energy requirement. 

Blackman et al. [71] compared the use of conventional abrasion pretreatments with corona discharge and oxygen plasma treatments. Again, the need to optimise the surface polarity was confirmed. As in the previous work, both adhesive and matrix chemistry influenced the optimum plasma conditions. For carbon/PEEK... 

Figure 23 SEM micrographs of carbon/PEEK composites a) as moulded b) abraded and solvent cleaned c) corona treated (20J/mm ) d) oxygen plasma treated (10 min) (Courtesy Imperial College London).

Figure 24 SEM micrographs of Excimer-Laser ablated carbon/PEEK composites a) low energy (0.18 J/P cm, 100 pulses) b) high energy (1 J/P cm, 10 pulses) (Courtesy ...

In the case of carbon/PEEK system, the maximum temperature into the composite will be higher than the thermoset system (400° C). The resin and fibers were preheated from room temperature to 3(X)°C in order to melt the resin. For the case of glass/PP the temperature in the preheated section reached 150° C. In the taper section (he temperature reached 190° C. In both cases, the thermocouple location was in the superior comer of the composite cross section. The pulling velocity varied from 5 to 50 m/s. The pulling forces varied from 2.5 to 4 kN for carbon/PEEK system and it was lower for the case of gJass/PP composite (200-700 N). 

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