Even though composite materials are already used in the manufacturing of structural components in aeronautics industry a consequent light-weight design of CFRP primary structures is limited due to a lack of adequate joining technologies. In general, adhesive bonding is the optimum technique for joining CFRP light-weight structures, but difficulties in assessing the bond quality by non-destructive testing (NDT) limit its use for aircraft structural assembly. In consequence certification by the regulation authorities is restrictive. In order to implement robust and reliable quality assurance procedures for adhesive bonding, the main objective of ENCOMB is the identification, development and adaptation of methods suitable for the assessment of the adhesive bond quality. Since the performance of adhesive bonds depends on the physico-chemical properties of adherend surfaces and adhesives, testing methods for adhesive and adherend surface characterisation will also be developed.

The implementation of reliable adhesive bonding processes by advanced quality assurance will lead to an increased use of light-weight composite materials for highly integrated structures minimising rivet based assembly. The expected weight savings for the fuselage airframe are up to 15 %. These weight savings will have further effects on the size and weight of the engines. From the overall weight savings, significant reductions in fuel consumption (direct costs) and hence CO2 emissions per passenger-kilometre will result. In ENCOMB, a multidisciplinary consortium of 14 partners from top-level European research organisations, universities and industries brings together leading experts from all relevant fields. The participation of three major European aircraft manufacturers as well as one SME ensures the consideration of relevant application scenarios, technological specifications and use of the full exploitation potential of the results.

For more information, you can view the ENCOMB project summary here.