The Effect of Room-Temperature Aging on Enthalpy and Dielectric Property of Carbon-Fiber/Epoxy Composite Prepreg and the Mechanical Property of Manufactured Composite

Abstract

**Please note that the full text is embargoed** ABSTRACT: Fiber-based reinforced plastics are widely used materials in different industries - e.g., Automotive, Aerospace, Defense- because of their various advantages. The most reliable raw materials for manufacturing fiber-based composites are pre-impregnated reinforcing fiber (prepreg). However, the limitation of using prepreg lies in its instability at room temperature. Prepregs have a specific out-life which sometimes makes the manufacturing process difficult. The objective of this study is to find out a way to investigate the room temperature aging effect on prepreg by analyzing the enthalpy and dielectric properties. In this study, differential scanning calorimetry (DSC) was used to measure the reaction enthalpy in the aged prepreg. The dielectric property of aged prepreg has also been analyzed using broadband dielectric spectroscopy (BbDS). We observed a significant effect on the enthalpy and dielectric properties of the aged prepreg. Furthermore, this study concentrates on how the aging of prepreg can affect the mechanical properties of the final composite parts. This study shows that the manufactured composite from aged prepreg shows inconsistency and a slight reduction in its tensile strength. Finally, a manufacturing strategy is suggested that will minimize the inconsistency of the strength of the final composite part manufactured from aged prepreg. [Copyright 2021. Used by the Society of the Advancement of Material and Process Engineering with permission. Proceedings of SAMPE neXus 2021, Virtual Event, June 29 – July 1, 2021, Society for the Advancement of Material and Process Engineering – North America.]