This work consists of evaluating the tensile and compression static allowable stress of a hybrid (metal-composite) riveted joint. The analyzed joint is composed by two sheets of 2014 – T6 aluminium alloy and a T300/5208 Graphite/Epoxy quasi-isotropic laminate, which were joined by twelve Lockbolt Swaged Collar rivets titanium alloy Ti–6Al–4V annealed. The joint was analyzed through a computational model developed using the Finite Element Method (FEM), with the fasteners modelled through the Multi - Springs technique. This method was widely used to simulate the mechanical behaviour metal-metal and composite-composite parts of the joint. It is validated comparing its results with analytical results of metallic joints available in the literature. Through this model, both the allowable load and its distribution in the fasteners of the joint were determined. Since the evaluated joint is subjected to double shear and, therefore, has no eccentricities, the presence of secondary bending was not observed, the bearing and bypass loads were the most relevant in evaluating the allowable loads of the joint. The load distribution in the joint and its components’ safety margin was determined, with the laminate being the limiting component of the allowable load.

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The procedure of structural design for aircraft parts is widely known and discussed in the academy and in the industry, although it has been improved along the time. It is based on a detailed process of aerodynamics loads study coupled or not with specifications required by regulatory agencies. Further, several interactions of analysis are done to define the critical stress state of the structure submitted to load conditions, because it is a complex structure that needs to be often improved and updated (considering the requirement of assembly/disassembly simplicity). There are several components in an aircraft attached to each other by the use of fasteners, rivets or nuts made of different materials (aluminum, steel, Inconel among others). In fact, it is not to easy to obtain stress state of the aeronautical structure for real loading conditions. Further, it is also difficult to calculate the load acting on each one of the joints. Several studies were already performed in order to obtain the correct understanding of how actual loads is distributed through the joints. The present work aims to compare results in aircraft joints (focusing in spar and skin regions), considering three levels of fidelity to understand the differences in the structural response using different type of modeling approach. Finite Element Analysis modelings made using Nastran software were performed. Preliminary results show good response agreement even for high and intermediate detail levels. Low detail level present promisor response as a tool for predesign.

Este artigo tem como objetivo apresentar um estudo sobre o comportamento à absorção de energia ao impacto de dois tipos de componentes: um núcleo de estrutura sanduíche em formato de honeycomb e um atenuador de impacto automotivo, ambos de alumínio. Para tal, são realizadas simulações numéricas pelo método dos elementos finitos, utilizando o programa comercial Abaqus. Os componentes são modelados com elementos finitos do tipo casca (shell) sendo que, para cada um dos componentes, foram construídos dois modelos numéricos: um sem e outro com a consideração de dano. As curvas força versus deslocamento e valores de parâmetros relacionados à capacidade de absorção de energia de impacto dos modelos dos componentes, obtidos como resultados das simulações, são apresentados e discutidos.