Functionally graded adhesive joints – A review and prospects

Abstract

There is increasing demand for effective and efficient lightweight structures because of global environmental and resource sustainability concerns. Adhesive bonding has been adopted in many assembly arrangements because of its relative reduction of stress concentration in joints compared to mechanical fasteners. Functionally graded bonded joints presents even greater potentials for reduction of stress concentrations and the tailoring of stress distribution as may be desired in an adhesive layer. This capability provides opportunity for the design of high performance tailored structural assemblies. Although some encouraging analysis and experimental work have been carried out on the development of functionally graded joints, its wide application is still to be realised. This paper reviews the work that has been carried out so far on the method, in terms of analysis, fabrication, experimental testing and application. It also reflects on outstanding issues that need to be resolved in order for wider application to be feasible.

A comparison between macro-element and finite element solutions for the stress analysis of functionally graded single-lap joints

“…The interest in FGAs has increased in recent years [9][10]. FGA joints involve a continuous variation of the adhesive properties along the overlap allowing for the homogenization of the stress distribution and load transfer.…”

Simplified stress analysis of functionally graded single-lap joints subjected to combined thermal and mechanical loads

“…The mixed adhesive solution which is a rough version of a graded joint consists in the use of various different adhesives along the overlap to increase the joint strength [10][11][12][13]. In recent past years, functionally graded adhesive (FGA) have been more and more considered [14][15]. FGA joints involve a continuous variation of the adhesive properties along the overlap allowing for the homogenization of the stress distribution and load transfer.…”

On the Potential Static Strength of Hybrid (Bolted/Bonded) Lap Joints with Functionally Graded Adhesives

“…The interest in functionally graded adhesive (FGA) joints has been increasing in recent years [21][22][23][24]. FGAs offer the opportunity to optimize the strength of multi-material bonded joints by locally tailoring the adhesive properties and without modifying the design of the adherends to be joined.…”

“…FGA joints involve a continuous variation of the adhesive properties along the overlap allowing for the homogenization of the stress distribution and load transfer. Manufacturing methods of FGA joints can be found in [24][25][26].…”