Influence of Line Processing Parameters on Properties of Carbon Fibre Epoxy Towpreg

Abstract

This paper explores the performance of low-cost unidirectional carbon fibre towpregs with respect to line production speed and fibre volume fraction. Using an automated production line, towpregs were produced at different production speeds, resulting in modified fibre volume fractions. The towpregs were used to manufacture unidirectional composite plates, which were then tested to evaluate mechanical performance. The fibre straightness and interfacial void ratio of the composite plates were determined by statistical analysis of the samples’ optical micrographs. The results demonstrate that adjusting the line production speed enables targeted fibre volume fractions (FVF) to be reached, resulting in the composites having different mechanical performances (2039 MPa and 2186.7 MPa tensile strength, 1.26 and 1.21 GPa flexural strength for 59.8% and 64.4% FVF, respectively). It was shown that at lower production speeds and FVF, composites exhibit good consolidation and low porosity, which is highlighted by the better interlaminar shear strength performances (8.95% increase), indicating the limitations of manufacturing very high FVF composites. Furthermore, it was concluded that fibre straightness plays a key role in mechanical performance, as samples with a lesser degree of fibre straightness showed a divergence from theoretical tensile properties.

A Novel Method of Jacobian Contours to Evaluate the Influence Line in Statically Determinate Structures

“…The following Figure 11 represents, step by step, an application of the Jacobian method to a statically determined structure. The first case is for the internal moment, the second case is for the shear force, and the last is for the normal force [35][36][37].…”

A Review on the Cost Analysis of Hydrogen Gas Storage Tanks for Fuel Cell Vehicles

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Solid epoxy prepregs with patterned resin distribution: Influence of pattern and process parameters on part quality in vacuum‐bag‐only processing

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“…They investigated options to overcome these challenges, such as melting, during forming or application of a water‐based gel, however, they were either impracticable, economically inefficient, or resulted in insufficient part quality 17 . Recent research is re‐addressing the development and processing of carbon fiber (CF) yarns impregnated with SR 19–21 …”