A Method for Optimal Blank Shape Determination in Sheet Metal Forming Based on Numerical Simulations

Abstract

The main benefit of using optimally shaped blanks in sheet metal forming is to maximize the efficiency of the forming process and, since there is no need for additional cutting operations after the finished forming operation, this leads to a substantial reduction in overall production costs. This paper presents a numerical method for optimal blank shape determination, which is suitable in various sheet metal forming applications. The optimal blank shape is determined in an iterative way so that the edge geometry of the formed product fits its reference geometry as closely as possible. The iterative process starts with the blank shape from which the product is produced with its edge fitting its reference geometry just approximately. In subsequent iterations, the blank shape is continuously improved in accordance with the developed optimisation method. In order to determine the product edge geometry resulting from the given blank shape, a computer simulation of the forming process and related springback is performed at each iteration. Since its effectiveness greatly depends on the quality and physical objectivity of the computer simulation, the developed numerical blank shape optimisation procedure has also been validated experimentally by using the forming of a product with a rather complex edge geometry as the case study.

A Method for Simultaneous Optimization of Blank Shape and Forming Tool Geometry in Sheet Metal Forming Simulations

“…In Mole et al [52], we developed a geometric mapping method similar to the push/pull technique. One thing common to all the previously mentioned methods is that the blank must be re-meshed after its shape correction.…”

Identification of Out-of-Plane Material Characteristics through Sheet-Metal Blanking

“…Therefore, sheet-metal blanking would offer similar options to the shear-punch testing, resulting in total separation of the sheet metal, and thus enabling fracture point determination. Furthermore, the identification and optimization of the blanking process, although one of the most frequently used industrial processes for sheet laminations, is mostly focused on the optimization of the tools [22] to [24] or electromagnetic properties of the finished part [25]. Therefore would a direct material characterization procedure enable further understanding and optimization of the process.…”

The Effect of the Thickness-to-Die Diameter Ratio on the Sheet Metal Blanking Process

“…Mole et al [19] proposed a new FEM method to optimize the blank shape. Behrens et al [20] focused on the effect of speed and clearance to the blank load and sheared surface geometry distribution.…”