MODELLING AND SIMULATION OF REINFORCED TAPES BEHAVIOUR FOR FORMING PROCESSES

MODELLING AND SIMULATION OF REINFORCED TAPES BEHAVIOUR FOR FORMING PROCESSES Muhammad. S. Saeed, Nils Widmaier, Boris. Eisenbart, Racim Radjef, Matthias. Kreimeyer, Peter. Middendorf 2 ─Modelling of near net shape 2D tape laminates. ─Definition of boundary conditions and process parameters for forming process. Speeds up development process Reduces costs Reduces need for physical prototypes Earlier Insights Better Products Faster Innovation Greater Productivity Higher ROI Why we Simulate? 3 ─Simulation without a test can lead to some model inaccuracies. ─Performing analyses at the physical level can be relatively simple. Why we Test it Physically? Increase modeling accuracy Speeds up design cycle Reduces defective prototypes Earlier Insights Better Products Faster Innovation Greater Productivity Higher ROI 4 Content ─Research Overview ─Modelling of Tapes ─Simulation of Tapes ─Validation of the Model ─Analysis and Discussion ─Conclusion 5 Overview ─Modelling and simulation of reinforced tape laminates can aid in supporting the early phase development of defect free formed part. Analysis of Tapes behaviour during forming process Forming Simulation for Carbon Fibre Reinforced Tape Laminates Forming Experiment for Carbon Fibre Reinforced Tape Laminate Shear & Fibre Angle Shear and fibre angle to observe formability Shear force –Spotweld Spotweld impact on the forming behaviour Fibre orientation Fibre direction depending on the material type Double Diaphragm Forming Simulation Double Diaphragm Forming Process 6 Modelling of Tapes ─Modelling of tapes is according to the Multilayer ─Modelling of spotwelds as per the standards of Multilayer such as the diameters of the spotweld No. of Spotweld: 60 Tape Size: 50 x 300 mm (Qty: 10) Tape Size: 50 x 500 mm (Qty: 6) No. of Spotweld: 28 No. of Spotweld: 52 Multilayer 7 Welding Spots Selected at a uniform Distance •Multilayer: Welding is done tape by tape for each layer (tape). •Visual Form: Welding points are selected tape by tape (layer by layer) replicated as Multilayer. 50mm Modelling of Spotwelds 8 Simulation of Tapes At Temperature 150°C Shear force – Spotweld Fibre Angle Fibre Orientation Shear Angle At Temperature 170°C 9 Simulation of Tapes At Temperature 150°C Shear force – Spotweld Fibre Angle Fibre Orientation Shear Angle At Temperature 170°C 16 Analysis and Discussion Vacuum pull: •Real Vacuum pull between lower diaphragm and tool different to expected pull in important major forming region due to pump regulator problems •It can also be seen in the simulation models, where the curve part of the double dome geometry is smooth during forming while the diaphragm changes the conditions. Springback: •Good forming behaviour overall •High springback of the preform •Possible reasons: non-symmetrical layup bridging leads to internal stressed built up which are partly released during cool down as explained during simulation model. Additional Vacuum foil used: •Silicon spray used on both Vacuum foil sheets facing the preform. This is to minimise sticking of the preform to the vacuum foil. •The Vacuum foil is being used to minimise sticking of the preform to the diaphragm material, to protect the diaphragm from thermoplastic residue and minimise than change of mechanicaly damaging the diaphragms (by e.g. cutting into them) 17 Conclusion At 170°C •Similar forming results between all weld spot configurations during experiments •Main defects wrinkles caused by diaphragm and spotwelds in 2 configurations •Slight flow of matrix, got adhesion between tapes Still: Probably higher temperature (and pressure?) necessary for full consolidation •Weld spots still visible from outside in the simulation model At 150°C •Close to lowest possible temperature (tg at 140°C) •Tapes stick only slighty together. Lift up and sometimes space between tapes visible •Weld spots still visible from outside and between tapes (When tapes are being pulled apart (if sticking together), weld spots are still clearly connected) •Forming Quality generally worse than with 170°C (e.g. wrinkles on top side of Doube Dome) •No major difference between weld spot configurations. (Slightly different wrinkles on side of double dome. Might require more detailed analysis to find differences in results. Thank you A/Prof. Dr. Boris Eisenbart Director of the Testlab beisenb[email protected] Dr. Racim Radjef Research Engineer rradje[email protected] Prof. Dr. Matthias Kreimeyer Head of “Product Development and Design Technology” [email protected] Muhammad Shahrukh Saeed PhD Candidate –GIL Project Swinburne University of Technology University of Stuttgart [email protected] Prof. Dr. Peter Middendorf Head of “Institute of Aircraft Design” peter.middend[email protected]stuttgart.de Nils Widmaier PhD Candidate –GIL Project Swinburne University of Technology University of Stuttgart [email protected].au