Numerical Simulation Of3D Stretching Of Sheet Metal With Micro Groove

Stretch forming of sheet metal with micro groove, processing the micro groove sheetinto a three-dimensional curved part, was combination of the drag reduction of microgrooves and stretch forming process, which could easily realize the drag reduction. It wasstudied that compared with the smooth the formability of micro groove sheet was affectedor not, and if the twist was appeared in the stretch forming of sheet metal with microgrooves. The main points of the study were as follows:1. In the paper, the influence of micro grooves to the tensile properties was studiedthrough uniaxial tensile experiment, and finite element model was established by usingfinite element software. For different groove direction sheet, smooth surface sheet anddifferent grooves sheet uniaxial tensile experiments was conducted separately, it wasdetermined that the forming effect of micro groove sheet with different groove directions,the influence of micro groove to sheet formability and the formability of sheets withdifferent morphology grooves. Combined with the experiment and simulation, it wasfound that when the micro groove sheet was processed from plate sheet the formabilitywould be affected by the micro grooves and the tensile limit would be lower as well. Theelongation along the groove direction was bigger than that in vertical direction and thegroove morphology had some influence to formability, different geometric morphologywould lead to different sheet formability.2. For the stretch forming process of saddle, cylindrical and spherical parts, thecorresponding finite element model were built and the numerical simulations wereconducted as well. The results shown that the elongation along the groove direction wasbigger than that in vertical direction and the grooves would have a bigger deformation invertical direction. The tensile limit of sheet with grooves was smaller than that of smoothsurface sheet, and the sheets with different geometrical morphology of micro grooves haddifferent tensile limits, which is related to the geometrical morphology and spacing ofgrooves. When the sheet with micro grooves was processed into3D curved part by stretchforming, the micro groove would have a bending tilt along the curvature center directionand its depth would change as well, and the groove with different geometricalmorphology had different change. With the decrease of curvature radius and the increase of elongation, the groove depth would have a bigger change, if there was a big curvatureradius,there would have a serious tilt distortion in local groove.3. For different geometrical morphology of micro groove, the correspondingspring-back simulation was conducted. The results shown that the spring-back of sheetwith micro grooves was larger than that of smooth sheet, different geometricalmorphology had different spring-back and there was bigger groove spacing, there was alager spring-back.The research methods and conclusions in the paper would had some certain guidingsignificance to the3D curved forming and the further study on the drag reduction of sheetwith micro grooves, which would lay a foundation for the application of3D curvedsurface parts with micro grooves.