Demonstration of the Application of Superplastic Forming Using Infrared Heating Emitters to a Part of Structure Including Various Geometrical Singularities

Abstract

ArianeGroup and Aurock led a feasibility study through the realization of a scale 1 TA6V demonstrator, using superplastic forming (SPF). ArianeGroup designed the demonstrator according to its knowledge of representative structures, comprising singularities: welds, stiffeners and areas with important thicknesses variations. Aurock performed first numerical simulations of the complete process, putting in evidence the various difficulties to be solved. Then, the demonstrator was physically carried out. Once the demonstration was virtually obtained, each steps of the process were experimented: welding of thick plates with limited deformation, machining of flat panels, pre-forming by rolling and final SPF. For the SPF step, a heating cover and a reinforced refractory castable die were manufactured. Infrared emitters’ position and heating power regulation laws were carefully defined, for the panel to be kept at the correct temperature until being formed. The SPF step led to a successful demonstration of the representative structure. The experimental approach confirmed the process modelling predictability. Limited Scale 1 demonstration was necessary to ensure the process validity with real thicknesses and thickness variations, which are known to mask problems if scale reductions are used without precautions. This methodology can be transfer to a real structure only by tooling adaptations, without additional feasibility works.