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Abstract(s)
A tecnologia de ligação por adesivos tem vindo a ser utilizada ao longo de várias décadas, permitindo solucionar diversos problemas associados a técnicas mais tradicionais, como soldadura a rebitagem ou as ligações aparafusadas. Trata-se de uma alternativa viável devido a diversos fatores como o menor peso estrutural, menor custo de fabricação e a capacidade de união de diferentes materiais.
O crescente recurso a materiais compósitos em diversas indústrias, nomeadamente a aeronáutica e naval levaram ao consequente aumento da aplicação de juntas adesivas, por serem indicadas como forma de união destes materiais, onde é de enaltecer a sua elevada resistência á fadiga.
Este trabalho pretende estudar a influencia de vários fatores da simulação na avaliação do estado de tensão nas juntas adesivas com matérias hiperelásticos.
O material hiperelástico em estudo foi o polidimetilsiloxano (PDMS).
Para isso, inicialmente foi necessário efetuar alguns ensaios experimentais para caracterizar o comportamento mecânico do material. Com base nesses resultados foram realizadas várias simulações numéricas com os modelos constitutivos mais comuns na simulação de materiais hiperelásticos, variando fatores numéricos e parâmetros das juntas adesivas.
Na análise feita foi utilizado um código de elementos finitos comercial denominado ANSYS.
No final os resultados obtidos da simulação foram comparados utilizando para o efeito gráficos de fácil perceção, a fim de ser notória a influencia dos parâmetros no estado de tensão das juntas adesivas.
The technology of engineering adhesives has been used over several decades, in order to solve the problems related to more traditional technical solutions, such as riveting weld or bolted joints. This is a viable alternative due to several factors such as the lowest structural weight, the lowest-cost production, and the bonding capacity of different materials. The increasing use of composite materials in several industries, namely the aircraft and marine engineering, have led to a consequent increase in adhesive joints implementation, because they are considered the joining of these materials, whose high resistance to fatigue should be validated. This study aims at studying the influence of a number of factors regarding the simulation in the condition assessment of stress fields in adhesive joints with hyper-elastic materials. The hyper-elastic material was the polydimethilsiloxane (PDMS). To do this, it was necessary to perform some experimental tests to characterize the mechanical behaviour of the material. Based in these results, numerical simulations have been performed, using the most common constitutive models in the hyper-elastic materials simulation, with numeric variables and adhesive joints parameters. The assessment used a code of commercial finite elements named ANSYS. In the end, the results obtained were compared using very easy to read intuitive charts with a view to laying down the clear parameters influence of the stress state of adhesive joints.
The technology of engineering adhesives has been used over several decades, in order to solve the problems related to more traditional technical solutions, such as riveting weld or bolted joints. This is a viable alternative due to several factors such as the lowest structural weight, the lowest-cost production, and the bonding capacity of different materials. The increasing use of composite materials in several industries, namely the aircraft and marine engineering, have led to a consequent increase in adhesive joints implementation, because they are considered the joining of these materials, whose high resistance to fatigue should be validated. This study aims at studying the influence of a number of factors regarding the simulation in the condition assessment of stress fields in adhesive joints with hyper-elastic materials. The hyper-elastic material was the polydimethilsiloxane (PDMS). To do this, it was necessary to perform some experimental tests to characterize the mechanical behaviour of the material. Based in these results, numerical simulations have been performed, using the most common constitutive models in the hyper-elastic materials simulation, with numeric variables and adhesive joints parameters. The assessment used a code of commercial finite elements named ANSYS. In the end, the results obtained were compared using very easy to read intuitive charts with a view to laying down the clear parameters influence of the stress state of adhesive joints.
Description
Keywords
PDMS Material hiperelástico Juntas adesivas Simulações numéricas Estado de tensão