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This study investigates the influence of reduced graphene oxide (rGO) coated glass fabrics on the strain sensing and the mechanical characteristics of fiber‐reinforced composites. Graphene oxide was applied in two thicknesses (threefold and fivefold coatings) onto a fabric using a padder mangle machine followed by thermal reduction and infused with an epoxy to manufacture rGO‐enhanced composite. The tensile modulus and flexural strength of the rGO‐enhanced composites with threefold coating were improved by 27% and 6.2%, respectively, compared with the equivalent composite manufactured without rGO. The normalized resistance (ΔR/R0) of composites increased by 0.89% and 3.48% under a cyclic tensile force of 1000 and 4000 N. The magnitude of ΔR/R0 was stable within 30 cycles suggesting a consistent strain sensing performance with a gauge factor of 15.55. The electrical response of the rGO‐enhanced composite was evaluated using a new industrial standard for sensors, by assessing calibration curves. The composite showed low hysteresis and low electrical viscosity which make these materials suitable for industrial piezoresistive strain sensors. [ABSTRACT FROM AUTHOR]

• Measured through-thickness thermal conductivity of 2 × 2 twill carbon fabric using C-Therm Trident system with MTPS sensor. • Thermal conductivity is reduced by 38% under vacuum, attributed to presence of air in the porous structure of the fabric. • Layup thickness/configuration have negligible impact on thermal conductivity due to limited heat penetration. • Higher fabric compaction increases thermal conductivity owing to improved fibre nesting and contact. For high-fidelity simulation of heat transfer responses during various composite manufacturing processes involving heat, thermal conductivity (TC) of dry carbon weaves is essential. In this paper, the through-thickness TC properties of a 2 × 2 carbon twill weave are presented, employing a state-of-the-art C-Therm Trident module equipped with a Modified Transient Plane Source (MTPS) sensor. The effects of air presence, layup thickness, layup configuration, and fabric compaction on TC are investigated. Results reveal negligible impacts of layer number and configuration on TC. However, TC is significantly influenced by air presence and stack compaction. These findings provide improved comprehension of heat transfer in textile composites for more accurate process modelling and simulation using homogenized models. [ABSTRACT FROM AUTHOR]

In this study, the isothermal crystallization of poly (lactic acid) (PLA) and its graphene-based nanocomposites (containing 0.5, 1, 2, and 3 wt% of graphene nanoplatelets – GNp) was studied at 135°C under quiescent and different presheared conditions (0.1, 0.3, 0.5, 1.1, and 1.8 s for 60s). Induction time of crystallization was determined from the plot of storage modulus versus time in time sweep test. Results showed that increase in GNp content decreased the induction time significantly. The preshear flow did not significantly affect the induction time of PLA containing 0.5 wt% of GNp and neat PLA. However, an increase in the intensity of preshear for graphene-based nanocomposites containing 1, 2, and 3 wt% of GNp first decreased the induction time and then increased it. The induction time also decreased with increase in the duration of shear flow. [ABSTRACT FROM AUTHOR]

In this study, the electromechanical properties and strain monitoring behavior of graphene-coated glass fiber reinforced epoxy (GGFRE) composites were investigated. Glass fabrics were first coated with 2 wt% graphene dispersions using a blade coating method and composites of these graphene-coated glass fabrics were manufactured using vacuum resin infusion. As-prepared GGFRE showed an increase in normalized resistance (ΔR/R 0) by 4.46%, 10.5%, 11.07% and 11.27% proportional to the applied cyclic tensile forces up to 2000N, 3000N, 4000N and 5000N, respectively. The corresponding gauge factors were calculated to be 14.56 ± 1, 13.32 ± 1, 11.23 ± 0.5 and 8.69 ± 2, respectively. It was also observed that under cyclic tensile loadings at 2000N, ΔR/R 0 values were consistent within 11 cycles indicating a reliable sensing performance. The integration of graphene into the composite has shown to decrease the tensile strength as well as flexural strength and flexural modulus by 26%, 37% and 39%, respectively. This drop is believed to be caused by the lower fiber volume content in the GGFRE compared to that of the neat glass fiber composite and the ineffective interfacial interaction between the glass fiber and the graphene dispersion. The piezo-resistive behavior indicated by GGFRE along with their scalable manufacturing method suggest them as promising potential candidates for strain sensing applications. [Display omitted] [ABSTRACT FROM AUTHOR]