2010 · 25 citations · 0 references
EngineeringAerospace EngineeringMaterials ScienceAircraft StructuresStructural EngineeringStructural MaterialsAdhesive BondingDurabilityStructural CertificationStructural IntegrityStructural TestingAdhesive Failure ModesAirworthinessBond Failure ModesBond StrengthDesign AirworthinessFailure Mode AssessmentInterfacial FailureStructural Airworthiness
Summary This paper explains the mechanisms of formation and degradation of adhesive bonds, and how a degrading interface can cause a transition from a strong bond which fails by cohesion to a weak bond which fails by adhesion. Importantly, the mechanisms proposed also explain mixed-mode failures and the implication of these failures to the strength of adhesively bonded structures. The paper discusses the impact of adhesion and mixed-mode failures on the regulatory framework for certification and continuing airworthiness management of adhesive bonded aircraft structure. It outlines the difficulties in quantifying mixed-mode failures and how a lack of understanding of this failure mode has led to erroneous findings. A methodology is proposed which has the potential to prevent adhesion and mixed-mode failures from occurring.