Improved thermal and mechanical properties of carbon fiber filled polyamide 46 composites

The thermal and mechanical properties of polyamide 46 (PA46) filled with carbon fiber (CF/PA46) composites were studied. CF/PA46 was fabricated by the method of melt blending and injection molding. The results showed that thermal conductivity, tensile strength and impact strength of the composite increased with the increase of weight fraction of CF, however, the elongation at the break decreased as its weight fraction increased. The addition of CF had little effect on the melting temperature of composites, while the crystallization onset (T-o) and crystallization peak (T-p) temperatures of composites shifted to higher points. The scanning electron microscope images showed that when the weight fraction of CF was increased, the CF was more likely to form thermal chains and a network. When the CF weight fraction was 40%, thermal conductivity was 1.49 W/(m.K), approximately 5.54 times as high as that of the pure PA46, and the thermal diffusivity was 0.9755 mm(2)/s, 6.5 times higher than that of the pure matrix. Comparing the experimental data with the three expected thermal conduction models data, the Maxwell-Eucken thermal conduction model was considered more suitable for the PA46/CF composite, in which the weight fraction of the filler was <10% in the thermal conductive system.