Deep drawing simulation of Tailored Blanks

Tailored blanks are increasingly used in the automotive industry. A tailored blank consists of different metal parts, which are joined by a welding process. These metal parts usually have different material properties. Hence, the main advantage of using a tailored blank is to provide the right material properties at specific parts of the blank. The movement of the weld during forming is extremely important. Unwanted weld displacement can cause damage to both the product and the tool. This depends mainly on the original weld position and the process parameters. However experimental determination of the optimum weld position is quite expensive. Therefore a numerical tool has been developed for simulations of tailored blank forming. The Finite Element Code Dieka is used for the deep drawing simulations of some geometrically simple products. The results have been validated by comparing them with experimental data and show a satisfactory correlation

Warm Deep Drawing of Aluminium Sheet

Aluminium sheet drawing processes can be improved by manipulating local flow behaviour\ud by means of elevated temperatures and temperature gradients in the tooling. Forming tests\ud showed that a substantial improvement is possible not only for 5xxx but also for 6xxx series\ud alloys. Finite element method simulations can be a powerful tool for the design of warm\ud forming processes and tooling. Their accuracy will depend on the availability of materials\ud models that are capable of describing the influence of temperature and strain rate on the flow\ud stresses. Two models, an adapted Nadai power law and a dislocation based Bergström type\ud model, are compared by means of simulations of a cup drawing process. Experimental\ud drawing test data are used to validate the modelling approaches, whereas the model parameters\ud follow from tensile tests

Equivalent drawbead performance in deep drawing simulations

Drawbeads are applied in the deep drawing process to improve the control of the material flow\ud during the forming operation. In simulations of the deep drawing process these drawbeads can be replaced by\ud an equivalent drawbead model. In this paper the usage of an equivalent drawbead model in the finite element\ud code DiekA is described. The input for this equivalent drawbead model is served by experiments or by a 2D\ud plane strain drawbead simulation. Simulations and experiments of the deep drawing of a rectangular product\ud are performed to test the equivalent drawbead model performance. The overall conclusion reads that a real\ud drawbead geometry can succesfully be replaced by the equivalent drawbead mode

The development of a finite elements based springback compensation tool for sheet metal products

Springback is a major problem in the deep drawing process. When the tools are released after the forming stage, the product springs back due to the action of internal stresses. In many cases the shape deviation is too large and springback compensation is needed: the tools of the deep drawing process are changed so, that the product becomes geometrically accurate after springback. In this paper, two different ways of geometric optimization are presented, the smooth displacement adjustment (SDA) method and the surface controlled overbending (SCO) method. Both methods use results from a finite elements deep drawing simulation for the optimization of the tool shape. The methods are demonstrated on an industrial product. The results are satisfactory, but it is shown that both methods still need to be improved and that the FE simulation needs to become more reliable to allow industrial application

Deep drawing simulations of Tailored Blanks and experimental verification

Tailored Blanks are increasingly used in the automotive industry.\ud A combination of different materials, thickness, and coatings can be welded\ud together to form a blank for stamping car body panels. The main advantage\ud of using Tailored Blanks is to have specific characteristics at particular parts\ud of the blank in order to reduce the material weight and costs.\ud To investigate the behaviour of Tailored Blanks during deep drawing, the\ud finite element code DiekA is used. In this paper, simulations of the deep\ud drawing of two products using Tailored Blanks are discussed. For\ud verification, the two products are stamped to gain experimental information.\ud The correlation between the experimental results and the simulation results\ud appears to be satisfactory

Effect of lubricant type on deep drawing ratio and drawing force during cylindrical cup deep drawing

Cylindrical cup deep drawing technology is used in various manufacturing processes. For example, it is used in the automotive industry to manufacture auto parts. It is also used in the manufacture of household items. Lubricants are used in metal forming, especially deep drawing, to reduce friction between the tool and the workpiece. As a result, lubrication reduces forming energy and forming steps, increases the drawing ratio and tool life, while preventing galling, seizure and surface damages to the products. In this paper, the main purpose was to increase the deep drawing ratio and reduce the drawing force by angling the die and blank holder, and investigated the effect of lubrication on the deep drawing process. The force required and quality of deep-drawn cylindrical steel cups. Two different lubricants mineral and solid lubricant were used as well as two different die angles between the die and the blank holder (α = 0o and 15o). The results shows that The Limit drawing ratio increased from 1.75 to 2.175 without failure, The oil lubricant shows better enhancement of the drawing ratio and reduced the maximum drawing forc