Carbon fibre laminates

Some properties of a polyimide carbon fibre laminate are given in Table 18.14. 

Fig. 6. Fracture toughnesses of carbon fibre laminates, with laminate angles indicated on the curves.

This structural chassis of box-like architecture is the framework designed to accomodate all MART-LIME subsystems. It is fabricated from a carbon fibre laminate of high elastic modulus and low coefficient of thermal expansion, internal to which is a conducting mesh for both electromagnetic insulation and grounding. 

Brunner AJ, Terrasi GP, Cartie DDR. Fatigue testing of Z-pin reinforced carbon-fibre laminates. In Proceedings 12th international conference on fracture ICF-12, paper no. 01199 2009. pp. 1-8. 

We can predict the distribution of moismre in a laminate using Fickian diffusion kinetics. Figme 12.3 shows the calculated distribution of moisture in a carbon fibre laminate of thickness 0.94 mm after 3 days at 96% RH and 50 °C. As result of Fickian analysis, we can observe that it would take 13 years to reach equilibrium if the material had a thickness of 12 mm. However, this does not reflect the acmal environment since the temperature and RH can change. 

Figure 12.10 Moisture euhancemeDt after thermal spiking of carbon fibre laminates conditioned at 50 °C and 96% RH with 22 thermal spikes. Narmco Rigidite ( ) Fibredux 927D ( ) Fibredux 924C (o) [7].

Figure 14.1 Typical through penetration of a 3 mm carbon fibre laminate impacted with an energy of 40 J.

Figure 3.3(a) shows the predicted moisture absorption through the thickness of a carbon fibre laminate [5] after 3 days in 96% RH at 50 C. This illustrates the timescale of the diffusion process. Thus it can take 13 years in a composite laminate of thickness 12 mm before saturation is reached. In service, materials are subjected to variations in temperature and kinetic processes such as diffusion follow the Arrhenius law ... 

Impact behaviour, debonding and fatigue in carbon fibre laminates... 

Tucker [108] found that carbon fibre laminates acted as an extremely... 

Carbon fibre hazard concerns NASA, Aviation Week Space Technology, 47-50, Mar 5 1979. Cornwell AC, Initial tests on the effect of fire of carbon fibre laminates, RAE Technical Memorandum Mat, 354, 1980. 

Figure 1.6(b) The effect of fibre orientation on composite compressive strength. Measured for a 60 v/o, carbon fibre laminate. 

Table 10.5 Comparison of flexural strength of carbon fibre laminates and ratio of maximum fatigue stress to initial stress after 10 cycles... 

This general principle is as true for wooden substrates as it is for the high tech carbon fibre laminates. Indeed, it was with the bonding of wood in aircraft structures that the requirement for surface pretreatment first came to light. 

Figure 6.33 An example of holographic non-destructive testing. The test specimen was an adhesively bonded carbon fibre laminate honeycomb structure and a vacuum was applied to cause increased displacement of the face sheet when a defect was present. Debonds were present at the interface between the face sheet and honeycomb core (below the disturbance in the regular pattern that can be seen second from top and bottom) and crushed honeycomb core was also present (top and third from top) [149].

Nanofibres veils can be used in between carbon fibre laminate to significantly improve the following mechanical properties [95] of carbon fibre reinforced plastic materials. 

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