Role of a gradient interface layer in interfacial enhancement of carbon fiber/epoxy hierarchical composites

• Published in: Journal of materials science Vol. 50; no. 1; pp. 112 - 121
• Main Authors: Chen, Lei, Jin, Hao, Xu, Zhiwei, Li, Jialu, Guo, Qiwei, Shan, Mingjing, Yang, Caiyun, Wang, Zhen, Mai, Wei, Cheng, Bowen
• Format: Journal Article
• Language: English
• Published: Boston Springer-Verlag 01.01.2015; Springer US; Springer; Springer Nature B.V
• Subjects: Analysis; Atomic force microscopes; Atomic force microscopy; Carbon fiber reinforced plastics; Carbon fibers; Carbon-epoxy composites; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; composite materials; Composite materials industry; Crystallography and Scattering Methods; Dispersion; epoxides; Graphene; Interfacial properties; Interfacial shear strength; Interphase; Liquid phase deposition; Liquid phases; Materials Science; Original Paper; Performance enhancement; Polymer matrix composites; Polymer Sciences; scanning electron microscopes; Scanning electron microscopy; Shear strength; Sheets; Solid Mechanics; Flexural Strength; Carbon Fiber; Interfacial Property; Graphite Oxide; Flexural Property
• ISSN: 0022-2461; 1573-4803
• DOI: 10.1007/s10853-014-8571-y

To improve the interfacial properties of carbon fibers/epoxy composites, we introduced a gradient interphase reinforced by graphene sheets between carbon fibers and matrix with a liquid phase deposition strategy. Interlaminar shear strength and flexural strength of the composites are both improved. The interfacial reinforcing mechanisms are explored by analyzing the structure of interfacial phase with linear scanning system of scanning electron microscope and atomic force microscope. Results indicate that carbon element shows a graded dispersion in the interface region and a gradient interface layer with the modulus decreasing from fibers and matrix is found to be built. To verify the effect of gradient interphase on the interfacial properties of composites, the mixture of carbon fiber/graphene/epoxy is sonicated before curing to disperse graphene sheets in matrix homogeneously. As a result, gradient interphase structures are disappeared and interfacial performance of composites is found to be weakened. The role of gradient interface layers in enhancing interfacial performances is further proved from a different angle.