| With the increment of the world’s demand, it is difficult for the electric power company to meet the cumsumers demand by upgrading the current transmission lines, so it is necessary to change the wire revolutionarily. Due to the excellent properties, carbon fiber composites are widely used in aerospace, automotive and infrastructure, glass/carbon fiber composite is used in power industry by some researchers, it is replaced the steel core, the hybrid composite can load more power to satisfy the consumers demand. But the hybrid composite core can generate defacts when produced and installed, and catastrophic rupture will occur. In order to increase safety of composite cable, more strands wire will be priority. The key techlonogies for the high reliable carbon fiber composite rope core are investigated in the present study, and the main contents are as follows:Three kinds multifunctional epoxy resins(AG-70, AG-80 and AFG-90), two kinds curing agents(MHHPA and MNA) and accelerator selected to compose six resin systems, and the detailed thermal analysis are carried out, then obtained the main resin AG-80 and curing agent MHHPA. The thermal analysis and gelation time are investigated for AG-80/MHHPA mixed with accelerator and release agent, and finally the components for the composite rope core matrix are: AG-80:MHHPA: 2,4-EMI:INT-1890 M = 100:118.5:1.5:5. Non-isothermal DSC is studied to obtain the curing kinetic equation which is suitable for auto-catalytic two-parameter model. The gelation times at various temperatures are measured to set up the relationship between gelation time and operating temperature in order to guide the pultrusion process. And then the viscoelastic property is determined by DMA and specific heat can be obtained from non-isothermal DSC.The thermal property of composite with/without carbon fiber are investigated by non-isothermal DSC, due to the good thermal conductivity of carbon fiber and the diffusion of release agent, the apparent activation energy for AMEI/CF system is lower than that for AMEI system, as well as pre-exponential factor. The characteristic temperatures for AMEI/CF system are obtained by extrapolation, and the parameters of kinetic models are calculated, and then the pultrusion process parameters are guided from the characteristic tempareture equation and gelation time vs. temperature relationship. The thermal stability for AMEI/CF system is studied and it is shown excellent thermal stability at the fiber volume 58.8% below 300 oC. The thermal expansion of coefficient(CTE) is varied with the temperature and the CTE changed slightly at the fiber volume 58.8%. The viscoelastic property for AMEI/CF is conducted by DMA and the storage and loss moduli are changed slightly at the glassy stage ascribed to the stiffness of carbon fiber, and the values of moduli for AMEI/CF system are larger than those for AMEI system.The profiles of conversion and temperature at transient state for AMEI/CF system in the pultrusion die are simulated, it is found that the temparetures at three points in the same cross section are similar due to the good thermal conductivity of carbon fiber, and the temperature at the centerline of the die is nearly the same at different pultrusion velocity, and also profiles of conversion are nearly overlapped for different lines along the centerline.The bending property for AMEI/CF system is simulated, it is found that the von Mises stress and total displacement are linear to the load, and the von Mises stress is linear to the length, but the total displacement is the quadratic function of length, but the von Mises stress and total displacement are exponential function to the diameter which is shown more complex relationship between them, and finally the function expressions are listed. |
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