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AgradecimentosAgradeço primeiramente a DEUS que sempre me guiou e iluminou, colocando as pessoas certas em meu caminho.A minha família que sempre me incentivou a acreditar em meus sonhos, em especial aos meus irmãos pelas constantes conversas e mensagens de apoio durante esta jornada.Ao Prof. Drº. Gilmar Ferreira Batalha pelos conhecimentos adquiridos, pelo profissionalismo como professor e orientador, e também pela motivação e força durante este trabalho. ABSTRACTThis study aims to evaluate the forming technique fluidostatic expansion (bulge forming) through a die with multiple cavities. Two AA5083 alloy and Pb-60Sn specification were submitted to superplasticity process (superplastic forming) for checking different working parameters and comparison with the results in numerical simulation. One of the main conclusions is that the multidomo method was valid to study the superplastic phenomenon. The tests were performed using the constant pressure method, where it was possible to obtain variables such as stress, strain rate and the strain rate sensitivity index. An important implication of this process is the correct control of working time with shaped cavities in separate trials.

Superplastic forming (SPF) is a technique that takes advantage of metallic alloys with fine grain size presenting very high ductility and large deformations before rupture under certain conditions. There is a growing interest in this manufacturing process in different areas, such as: aeronautical, automotive and medical, due to the possibility of fabricating complex geometry, lightweight, and strong thin shell parts. The researchers employed an industrial size superplastic hot press and, aiming to start investigations in the field of superplastic forming, finite element simulation and material analysis. This paper presents one of a first works in this field: developing a numerical model and forming a titanium alloy dome. A finite element model was developed to obtain the pressure curve, used as input in the superplastic forming machine control and for thickness prediction. Results and comparisons between the formed part and numerical calculations are presented, as well as the main difficulties the institutions faced in this new research field.