Análise comparativa do retorno elástico bibliográfico, analítico e experimental em diferentes espessuras do aço LNE250

Abstract

Sheet metal bending is widely employed in the metalworking industry for the manufacturing of components requiring high dimensional accuracy. Among the phenomena inherent to this process, springback stands out for causing changes in the final geometry of the part after the forming load is removed, representing one of the main challenges to achieving high geometric precision. In this context, accurate springback prediction is essential for defining geometric compensation strategies and reducing rework and manufacturing costs. This study presents a comparative analysis of the springback behavior of LNE 250 steel sheets with thicknesses of 3.00 mm, 4.75 mm, and 6.35 mm, using bibliographic, experimental, and numerical approaches based on the Finite Element Method (FEM). Initially, tensile tests were carried out to determine the mechanical properties of the material, which were subsequently used in the analytical calculations and numerical modeling. Air bending tests were then performed under conditions representative of industrial manufacturing, and the final bending angles and bend radii were obtained through dimensional measurements. The experimental results confirmed the occurrence of springback for all sheet thicknesses evaluated, with angular recovery ranging from 0.23° to 4.83°, demonstrating the influence of sheet thickness on the magnitude of the phenomenon. The analytical models tended to underestimate springback, whereas the finite element simulations provided predictions that were in closer agreement with the experimental results. Therefore, it is concluded that the numerical approach constitutes a promising tool for springback prediction, provided that it is properly calibrated and validated for the specific material and processing conditions under investigation. [resumo fornecido pelo autor]