A THEORETICAL STUDY OF THE MECHANICAL INTERLOCKING ON THE BONDED COMPOSITE REPAIR

Abstract

Abstract: Bonded repair has been the primary maintenance way for composite aircraft structure. Mechanical interlocking, electrostatic adsorption and chemical bonding were employed to reveal the surface bonding mechanism and maintenance effect. However, it′s difficult to separate the three adhesion theories to study single-factor for the repair result. In this paper, fluorocarbon additive (CF) with low surface energy was used to form a CF film on the surface of laser-treated (LA-CF) and polish-treated (PO-CF) composite laminate. LSCM contact angle, XPS and lap shear test was applied to investigate morphologies and roughness (Sa), surface free energy, chemical property and adhesion strength, respectively. The results showed that PO-CF and LA-CF specimen did not change their morphologies and roughness. Howerver, the surface energy decreased to around 10 mJ/m² and the contact angle increased to around 115°. Deconvolution bands of the XPS C1s displayed the same peak location and intensity. Lap shear test revealed that the shear bonding strength of LA-CF was 8.1 MPa higher than that of the PO-CF specimen. It demonstrated that mechanical interlocking played a bigger role than electrostatic adsorption and chemical bonding in this mechanism research of interface combination.

Key words: carbon fibre reinforced polymer, bonded repair, mechanical interlocking, interface

CLC Number:

TB332

ZHANG Hua-zhong, YANG Wen-feng, LI Shao-long. A THEORETICAL STUDY OF THE MECHANICAL INTERLOCKING ON THE BONDED COMPOSITE REPAIR[J]. Fiber Reinforced Plastics/Composites, 2019, 0(8): 17-22.

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